Search Space Monitoring Method and Apparatus

ABSTRACT

A search space monitoring method allows a terminal to monitor a power saving signal in a search space in a scenario in which the power saving signal can be applied to a long discontinuous reception (DRX) cycle and a short DRX cycle. The method includes, when using the long DRX cycle, monitoring, by the terminal, the power saving signal in a first search space, and skipping monitoring the power saving signal in a second search space, where the power saving signal indicates power saving information of the terminal; and when using a short DRX cycle, monitoring, by the terminal, the power saving signal in the second search space, and skipping monitoring the power saving signal in the first search space.

TECHNICAL FIELD

This application relates to the field of communications technologies,and in particular, to a search space monitoring method and an apparatus.

BACKGROUND

To reduce power consumption of a terminal, a discontinuous reception(discontinuous reception. DRX) technology is introduced in acommunications system. In a connected DRX technology, a DRX cycle isconfigured for a terminal in radio resource control (radio resourcecontrol, RRC) connected (connected) mode. As shown in FIG. 1, the DRXcycle includes opportunity for DRX (opportunity for DRX) and on duration(on duration). In the on duration, the terminal monitors and receives aphysical downlink control channel (physical downlink control channel,PDCCH). In the opportunity for DRX, the terminal does not receive dataof a downlink channel, so as to reduce power consumption. It should benoted that the DRX cycle may be classified into a short DRX cycle and along DRX cycle.

Currently, the terminal needs to monitor a PDCCH-based power savingsignal at a specific location in the DRX cycle. In addition, the powersaving signal may be applied to the long DRX cycle and the short DRXcycle. In this way, for the terminal, a cycle for monitoring the powersaving signal in the long DRX cycle is different from a cycle formonitoring the power saving signal in the short DRX cycle.

In the conventional technology, a search space monitoring cycle isfixed. Consequently, a search space used to carry a power saving signalcannot be applied to both a long DRX cycle and a short DRX cycle, and aterminal cannot normally monitor the power saving signal. The industryhas not provided a corresponding solution to this technical problem.

SUMMARY

This application provides a search space monitoring method and anapparatus, so that a terminal can normally monitor a power saving signalin a search space in a scenario in which the power saving signal can beapplied to a long DRX cycle and a short DRX cycle.

According to a first aspect, a search space monitoring method isprovided, including: When using a long DRX cycle, a terminal monitors apower saving signal in a first search space, and does not monitor thepower saving signal in a second search space, where the power savingsignal is used to indicate power saving information of the terminal.When using a short DRX cycle, the terminal monitors the power savingsignal in the second search space, and does not monitor the power savingsignal in the first search space.

Based on the foregoing technical solution, when using the long DRXcycle, the terminal monitors the power saving signal in the first searchspace, and does not monitor the power saving signal in the second searchspace. When using the short DRX cycle, the terminal monitors the powersaving signal in the second search space, and does not monitor the powersaving signal in the first search space. In this way, the terminal cannormally monitor the power saving signal in the search space in ascenario in which the power saving signal can be applied to the long DRXcycle and the short DRX cycle. In addition, regardless of the long DRXcycle or the short DRX cycle, the terminal needs to monitor the powersaving signal in only one search space, so that a quantity of searchspaces that the terminal needs to monitor is reduced, and powerconsumption of the terminal is reduced.

According to a second aspect, a communications method is provided,including: When a terminal uses a long DRX cycle, a network device sendsa power saving signal in a first search space, and does not send thepower saving signal in a second search space, where the power savingsignal is used to indicate power saving information of the terminal.When the terminal uses a short DRX cycle, the network device sends thepower saving signal in the second search space, and does not send thepower saving signal in the first search space.

Based on the foregoing technical solution, in a scenario in which thepower saving signal can be applied to the long DRX cycle and the shortDRX cycle, the network device determines, based on a type of a DRX cycleused by the terminal, a search space for carrying the power savingsignal. Therefore, the network device sends the power saving signal onlyin a search space matching the DRX cycle used by the terminal, so thatthe terminal can detect the power saving signal in the correspondingsearch space, thereby scheduling power saving of the terminal by usingthe power saving signal. In addition, when the network device configurestwo search spaces (that is, the first search space and the second searchspace) for the terminal, in the technical solution of this application,because the network device sends the power saving signal in only onesearch space in one DRX cycle, correspondingly, the terminal alsomonitors the power saving signal in only one search space, therebyavoiding a conventional-technology problem of unnecessary powerconsumption caused because the terminal needs to monitor the two searchspaces simultaneously.

According to a third aspect, a search space monitoring method isprovided, including: When using a long DRX cycle, a terminal monitors apower saving signal in a search space based on a first group ofconfiguration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal.When using a short DRX cycle, the terminal monitors the power savingsignal in the search space based on a second group of configurationparameters of the search space.

Based on the foregoing technical solution, when using the long DRXcycle, the terminal uses the first group of configuration parameters ofthe search space, to meet a requirement of the terminal for a cycle ofmonitoring the power saving signal in the long DRX cycle. When using theshort DRX cycle, the terminal uses the second group of configurationparameters of the search space, to meet a requirement of the terminalfor a cycle of monitoring the power saving signal in the short DRXcycle. In other words, in a scenario in which the power saving signalcan be applied to the long DRX cycle and the short DRX cycle, for adifferent DRX cycle, the terminal may use a group of configurationparameters corresponding to the DRX cycle, to ensure that the terminalcan normally monitor the power saving signal in the search space.

According to a fourth aspect, a communications method is provided,including: When a terminal uses a long DRX cycle, a network device sendsa power saving signal in a search space based on a first group ofconfiguration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal.When the terminal uses a short DRX cycle, the network device sends thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

Based on the foregoing technical solution, in a scenario in which thepower saving signal can be applied to the long DRX cycle and the shortDRX cycle, the network device determines a corresponding group ofconfiguration parameters of the search space based on a type of a DRXcycle used by the terminal, so that a monitoring cycle of the searchspace can match the type of the DRX cycle used by the terminal. In thisway, the network device sends the power saving signal in the searchspace. Correspondingly, the terminal can normally monitor the powersaving signal in the search space.

According to a fifth aspect, a search space monitoring method isprovided, including: A terminal determines M candidate monitoringoccasions (monitoring occasion) of a search space, where M is a positiveinteger. The terminal determines N target monitoring occasions from theM candidate monitoring occasions based on a time domain location of onduration of a DRX cycle, where N is a positive integer less than orequal to M. The terminal monitors a power saving signal on the N targetmonitoring occasions in the search space, where the power saving signalis used to indicate power saving information of the terminal.

Based on the foregoing technical solution, the terminal determines thetarget monitoring occasion based on the time domain location of the onduration of the DRX cycle. To be specific, when the terminal uses a longDRX cycle, the terminal may determine the target monitoring occasionbased on a time domain location of on duration of the long DRX cycle.When the terminal uses a short DRX cycle, the terminal may determine thetarget monitoring occasion based on a time domain location of onduration of the short DRX cycle. The target monitoring occasiondetermined by the terminal is adapted to a type of a DRX cycle used bythe terminal. In this way, regardless of the long DRX cycle or the shortDRX cycle, the terminal can normally monitor the power saving signal inthe search space on a proper monitoring occasion (that is, the targetmonitoring occasion).

In a possible design, a monitoring cycle of the search space is the sameas a short DRX cycle in terms of a time length. In this way, complexityof determining the target monitoring occasion by the terminal isreduced.

According to a sixth aspect, a communications method is provided,including: A network device determines M candidate monitoring occasionsof a search space, where M is a positive integer. The network devicedetermines N target monitoring occasions from the M candidate monitoringoccasions based on a time domain location of on duration of a DRX cycle,where N is a positive integer less than or equal to M. The networkdevice sends a power saving signal on the N target monitoring occasionsin the search space, where the power saving signal is used to indicatepower saving information of a terminal.

Based on the foregoing technical solution, in a scenario in which thepower saving signal can be applied to a long DRX cycle and a short DRXcycle, when the terminal uses the long DRX cycle, the network devicedetermines the target monitoring occasion based on a time domainlocation of on duration of the long DRX cycle. When the terminal usesthe short DRX cycle, the network device determines the target monitoringoccasion based on a time domain location of on duration of the short DRXcycle. The target monitoring occasion determined by the network deviceis adapted to a type of a DRX cycle used by the terminal. The networkdevice sends the power saving signal on the target monitoring occasion,so that the terminal can normally monitor the power saving signal on thetarget monitoring occasion.

According to a seventh aspect, a communications apparatus is provided.The communications apparatus may be a terminal, a chip in the terminal,or a system on chip. The communications apparatus includes a processorand a memory. The memory stores instructions. When the instructions areexecuted by the processor, the communications apparatus is enabled toperform the following steps: when using a long DRX cycle, monitoring apower saving signal in a first search space, and skipping monitoring thepower saving signal in a second search space, where the power savingsignal is used to indicate power saving information of the terminal; andwhen using a short DRX cycle, monitoring the power saving signal in thesecond search space, and skipping monitoring the power saving signal inthe first search space.

According to an eighth aspect, a communications apparatus is provided.The communications apparatus may be a network device, a chip in thenetwork device, or a system on chip. The communications apparatusincludes a processor and a memory. The memory stores instructions. Whenthe instructions are executed by the processor, the communicationsapparatus is enabled to perform the following steps: when a terminaluses a long DRX cycle, sending a power saving signal in a first searchspace, and skipping sending the power saving signal in a second searchspace, where the power saving signal is used to indicate power savinginformation of the terminal; and when the terminal uses a short DRXcycle, sending the power saving signal in the second search space, andskipping sending the power saving signal in the first search space.

According to a ninth aspect, a communications apparatus is provided. Thecommunications apparatus may be a terminal, a chip in the terminal, or asystem on chip. The communications apparatus includes a processor and amemory. The memory stores instructions. When the instructions areexecuted by the processor, the communications apparatus is enabled toperform the following steps: when using a long DRX cycle, monitoring apower saving signal in a search space based on a first group ofconfiguration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal; andwhen using a short DRX cycle, monitoring the power saving signal in thesearch space based on a second group of configuration parameters of thesearch space.

In a possible design, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following step: receiving configuration information of the searchspace, where the configuration information of the search space is usedto indicate the first group of configuration parameters and the secondgroup of configuration parameters.

In a possible design, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following steps: receiving configuration information of the searchspace, where the configuration information of the search space is usedto indicate a parameter other than a monitoring cycle and a monitoringoffset value in the first group of configuration parameters, and aparameter other than a monitoring cycle and a monitoring offset value inthe second group of configuration parameters; and receiving indicationinformation, where the indication information is used to indicate themonitoring cycle and the monitoring offset value in the first group ofconfiguration parameters, and the monitoring cycle and the monitoringoffset value in the second group of configuration parameters.

According to a tenth aspect, a communications apparatus is provided. Thecommunications apparatus may be a network device, a chip in the networkdevice, or a system on chip. The communications apparatus includes aprocessor and a memory. The memory stores instructions. When theinstructions are executed by the processor, the communications apparatusis enabled to perform the following steps: when a terminal uses a longDRX cycle, sending a power saving signal in a search space based on afirst group of configuration parameters of the search space, where thepower saving signal is used to indicate power saving information of theterminal; and when the terminal uses a short DRX cycle, sending thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

In a possible design, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following step: sending configuration information of the searchspace to the terminal, where the configuration information of the searchspace is used to indicate the first group of configuration parametersand the second group of configuration parameters.

In a possible design, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following steps: sending configuration information of the searchspace to the terminal, where the configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters;and sending indication information to the terminal, where the indicationinformation is used to indicate the monitoring cycle and the monitoringoffset value in the first group of configuration parameters, and themonitoring cycle and the monitoring offset value in the second group ofconfiguration parameters.

According to an eleventh aspect, a communications apparatus is provided.The communications apparatus may be a terminal, a chip in the terminal,or a system on chip. The communications apparatus includes a processorand a memory. The memory stores instructions. When the instructions areexecuted by the processor, the communications apparatus is enabled toperform the following steps: determining M candidate monitoringoccasions of a search space, where M is a positive integer; determiningN target monitoring occasions from the M candidate monitoring occasionsbased on a time domain location of on duration of a DRX cycle, where Nis a positive integer less than or equal to M; and monitoring a powersaving signal on the N target monitoring occasions in the search space,where the power saving signal is used to indicate power savinginformation of the terminal.

According to a twelfth aspect, a communications apparatus is provided.The communications apparatus may be a network device, a chip in thenetwork device, or a system on chip. The communications apparatusincludes a processor and a memory. The memory stores instructions. Whenthe instructions are executed by the processor, the communicationsapparatus is enabled to perform the following steps: determining Mcandidate monitoring occasions of a search space, where M is a positiveinteger; determining N target monitoring occasions from the M candidatemonitoring occasions based on a time domain location of on duration of aDRX cycle used by a terminal, where N is a positive integer less than orequal to M; and sending a power saving signal on the N target monitoringoccasions in the search space, where the power saving signal is used toindicate power saving information of the terminal.

According to a thirteenth aspect, a communications apparatus isprovided. The communications apparatus may be disposed on a terminal, ormay be a part of the terminal, or the terminal. The communicationsapparatus may include an apparatus, a unit, or a module configured toperform the method steps in the first aspect or the various designs ofthe first aspect. For example, the communications apparatus may includea first processing unit and a second processing unit. The firstprocessing module is configured to: when the terminal uses a long DRXcycle, monitor a power saving signal in a first search space, and skipmonitoring the power saving signal in a second search space, where thepower saving signal is used to indicate power saving information of theterminal. The second processing module is configured to: when theterminal uses a short DRX cycle, monitor the power saving signal in thesecond search space, and skip monitoring the power saving signal in thefirst search space.

According to a fourteenth aspect, a communications apparatus isprovided. The communications apparatus may be disposed on a networkdevice, or may be a part of the network device, or the network device.The communications apparatus may include an apparatus, a unit, or amodule configured to perform the method steps in the second aspect orthe various designs of the second aspect. For example, thecommunications apparatus may include a first communications module and asecond communications module. The first communications module isconfigured to: when a terminal uses a long DRX cycle, send a powersaving signal in a first search space, and skip sending the power savingsignal in a second search space, where the power saving signal is usedto indicate power saving information of the terminal. The secondcommunications module is configured to: when the terminal uses a shortDRX cycle, send the power saving signal in the second search space, andskip sending the power saving signal in the first search space.

According to a fifteenth aspect, a communications apparatus is provided.The communications apparatus may be disposed on a terminal, or may be apart of the terminal, or the terminal. The communications apparatus mayinclude an apparatus, a unit, or a module configured to perform themethod steps in the third aspect or the various designs of the thirdaspect. For example, the communications apparatus may include a firstprocessing module and a second processing module. The first processingmodule is configured to: when the terminal uses a long DRX cycle,monitor a power saving signal in a search space based on a first groupof configuration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal. Thesecond processing module is configured to: when the terminal uses ashort DRX cycle, monitor the power saving signal in the search spacebased on a second group of configuration parameters of the search space.

In a possible design, the communications apparatus further includes acommunications module. The communications module is configured toreceive configuration information of the search space, where theconfiguration information of the search space is used to indicate thefirst group of configuration parameters and the second group ofconfiguration parameters.

In a possible design, the communications apparatus further includes acommunications module. The communications module is configured to:receive configuration information of the search space, and receiveindication information. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

According to a sixteenth aspect, a communications apparatus is provided.The communications apparatus may be disposed on a network device, or maybe a part of the network device, or the network device. Thecommunications apparatus may include an apparatus, a unit, or a moduleconfigured to perform the method steps in the fourth aspect or thevarious designs of the fourth aspect. For example, the communicationsapparatus may include a first communications module and a secondcommunications module. The first communications module is configured to:when a terminal uses a long DRX cycle, send a power saving signal in asearch space based on a first group of configuration parameters of thesearch space, where the power saving signal is used to indicate powersaving information of the terminal. The second communications module isconfigured to: when the terminal uses a short DRX cycle, send the powersaving signal in the search space based on a second group ofconfiguration parameters of the search space.

In a possible design, the first communications module/the secondcommunications module is further configured to send configurationinformation of the search space to the terminal, where the configurationinformation of the search space is used to indicate the first group ofconfiguration parameters and the second group of configurationparameters.

In a possible design, the first communications module/the secondcommunications module is further configured to send configurationinformation of the search space to the terminal, and send indicationinformation to the terminal. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

According to a seventeenth aspect, a communications apparatus isprovided. The communications apparatus may be disposed on a terminal, ormay be a part of the terminal, or the terminal. The communicationsapparatus may include an apparatus, a unit, or a module configured toperform the method steps in the fifth aspect or the various designs ofthe fifth aspect. For example, the communications apparatus may includea first processing module and a second processing module. The firstprocessing module is configured to: determine M candidate monitoringoccasions of a search space, where M is a positive integer; anddetermine N target monitoring occasions from the M candidate monitoringoccasions based on a time domain location of on duration of a DRX cycle,where N is a positive integer less than or equal to M. The secondprocessing module is configured to monitor a power saving signal on theN target monitoring occasions in the search space, where the powersaving signal is used to indicate power saving information of theterminal.

According to an eighteenth aspect, a communications apparatus isprovided. The communications apparatus may be disposed on a networkdevice, or may be a part of the network device, or the network device.The communications apparatus may include an apparatus, a unit, or amodule configured to perform the method steps in the sixth aspect or thevarious designs of the sixth aspect. For example, the communicationsapparatus may include a processing module and a communications module.The processing module is configured to: determine M candidate monitoringoccasions of a search space, where M is a positive integer; anddetermine N target monitoring occasions from the M candidate monitoringoccasions based on a time domain location of on duration of a DRX cycleused by a terminal, where N is a positive integer less than or equal toM. The communications module is configured to send a power saving signalon the N target monitoring occasions in the search space, where thepower saving signal is used to indicate power saving information of theterminal.

According to a nineteenth aspect, a computer-readable storage medium isprovided. The computer-readable storage medium stores instructions. Whenthe instructions are run on a computer, the computer is enabled toperform the method in any design of the first aspect to the sixthaspect.

According to a twentieth aspect, a computer program product includinginstructions is provided. When the computer program product is run on acomputer, the computer is enabled to perform the method in any design ofthe first aspect to the sixth aspect.

According to a twenty-first aspect, a chip is provided. The chipincludes a processor, and when the processor executes instructions, theprocessor is configured to perform the method in any design of the firstaspect to the sixth aspect. The instructions may be from a memory insidethe chip, or may be from a memory outside the chip. Optionally, the chipfurther includes an input/output circuit.

For technical effects brought by any design of the seventh aspect to thesixteenth aspect, refer to technical effects brought by the foregoingcorresponding methods. Details are not described herein again.

According to a twenty-second aspect, a communications system isprovided, including a network device and a terminal. The terminal isconfigured to perform the search space monitoring method in any designof the first aspect, the third aspect, or the fifth aspect. The networkdevice is configured to perform the communications method in any designof the second aspect, the fourth aspect, or the sixth aspect.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of a DRX cycle;

FIG. 2 is a schematic diagram of a DRX cycle and a monitoring occasionof a search space:

FIG. 3 is a schematic diagram of an architecture of a communicationssystem according to an embodiment of this application;

FIG. 4 is a schematic diagram of a structure of a communicationsapparatus according to an embodiment of this application;

FIG. 5 is a flowchart of a search space monitoring method according toan embodiment of this application;

FIG. 6 is a schematic diagram of a DRX cycle and a monitoring occasionof a search space according to an embodiment of this application;

FIG. 7 is a schematic diagram of a scenario of communication between amobile phone and a base station according to an embodiment of thisapplication;

FIG. 8 is a schematic diagram of a scenario of communication between amobile phone and a base station according to an embodiment of thisapplication;

FIG. 9 is a flowchart of another search space monitoring methodaccording to an embodiment of this application;

FIG. 10 is another schematic diagram of a DRX cycle and a monitoringoccasion of a search space according to an embodiment of thisapplication;

FIG. 11 is a flowchart of another search space monitoring methodaccording to an embodiment of this application;

FIG. 12 is another schematic diagram of a DRX cycle and a monitoringoccasion of a search space according to an embodiment of thisapplication;

FIG. 13 is another schematic diagram of a DRX cycle and a monitoringoccasion of a search space according to an embodiment of thisapplication;

FIG. 14 is another schematic diagram of a DRX cycle and a monitoringoccasion of a search space according to an embodiment of thisapplication;

FIG. 15 is another schematic diagram of a DRX cycle and a monitoringoccasion of a search space according to an embodiment of thisapplication;

FIG. 16 is a schematic diagram of a structure of a communicationsapparatus according to an embodiment of this application;

FIG. 17 is a schematic diagram of a structure of a communicationsapparatus according to an embodiment of this application; and

FIG. 18 is a schematic diagram of a structure of a chip according to anembodiment of this application.

DESCRIPTION OF EMBODIMENTS

In the descriptions of this application, unless otherwise specified, “/”means “or”. For example, A/B may represent A or B. In thisspecification, “and/or” describes an association relationship fordescribing associated objects and represents that there may be threerelationships. For example, A and/or B may represent the following threecases: Only A exists, both A and B exist, and only B exists. Inaddition. “at least one” means one or more, and “a plurality of” meanstwo or more. Terms such as “first” and “second” do not limit a quantityand an execution sequence, and the terms such as “first” and “second” donot indicate a definite difference.

It should be noted that, in this application, the term such as “example”or “for example” is used to represent giving an example, anillustration, or descriptions. Any embodiment or design described as an“example” or “for example” in this application should not be explainedas being more preferred or having more advantages than anotherembodiment or design. Exactly, use of the term such as “example” or “forexample” is intended to present a related concept in a specific manner.

To facilitate understanding of the technical solutions of thisapplication, the following first briefly describes terms used in thisapplication.

1. PDCCH

The PDCCH is used to carry scheduling information and other controlinformation, for example, downlink control information (downlink controlinformation, DCI). The PDCCH includes a control channel element (controlchannel element, CCE).

2. DCI

The DCI may include content such as resource block (resource block, RB)allocation information and a modulation and coding scheme (modulationand coding scheme, MCS). Different DCI carries different information andhas different functions. To classify the DCI, a plurality of DCI formats(format) are defined in a protocol.

For example, a current communications standard defines the following DCIformats:

a DCI format 0-0: used to schedule uplink data of a terminal;

a DCI format 1-0: used to schedule downlink data of a terminal;

a DCI format 2-0: used to indicate a slot format; and

a DCI format 2-1: used to indicate interrupted transmission (interruptedtransmission).

The foregoing DCI formats are merely examples, and are not describedherein one by one.

3. Power Saving Signal (Power Saving Signal)

The power saving signal is used to indicate power saving information.The power saving signal may be used to implement power saving.

Optionally, the power saving signal is before on duration of a DRXcycle, and is used to indicate that a terminal is in a sleep state or anormal working state in the on duration of the DRX cycle associated withthe power saving signal. Optionally, bit information may be used in thepower saving signal to indicate that a terminal is in a sleep state or anormal working state in on duration of a DRX cycle associated with thepower saving signal. For example, one bit is used in the power savingsignal for indication. When the bit is ‘0’, it indicates that theterminal is in a sleep state; or when the bit is ‘1’, it indicates thatthe terminal is in a normal working state. In addition, the power savingsignal may be further used to indicate another function, for example,indicate the terminal to skip PDCCH monitoring (skipping PDCCHmonitoring), indicate the terminal to switch between bandwidth parts(bandwidth part, BWP), indicate secondary cell activation ordeactivation, or trigger channel state measurement.

Optionally, the power saving signal may be implemented based on a PDCCHor DCI. It should be noted that, when the power saving signal isimplemented based on the DCI, the power saving signal may be representedby using a specific DCI format. For example, in the embodiments of thisapplication, the power saving signal may be represented by using a DCIformat M. The power saving signal implemented based on the PDCCH hasadvantages of high reliability and low probability of missing or falsedetection.

The following describes the power saving signal by using an example withreference to an actual application scenario. For example, a user uses amobile phone to watch a video online. When the mobile phone needs tobuffer the video data, the mobile phone needs to monitor schedulinginformation sent by a base station, determine, based on the schedulinginformation sent by the base station, a time-frequency resource locationat which the “video data” is received, and obtain the video data at thecorresponding time-frequency resource location. When the mobile phonehas finished buffering the video data, the mobile phone does not need tomonitor the scheduling information sent by the base station. In thisapplication, when the base station finds that there is no data thatneeds to be sent to the mobile phone, that is, when the mobile phone hasfinished buffering the video data and does not need to monitor thescheduling information, the base station may send the power savingsignal to the mobile phone, to indicate the mobile phone not to monitorthe scheduling information in on duration of a next DRX cycle, therebyreducing power consumption of the mobile phone. On the contrary, if thebase station finds that there is data that needs to be sent to a targetuser, the base station may indicate the mobile phone to monitor thescheduling information in on duration of a corresponding DRX cycle byusing the power saving signal.

4. Search Space

The search space is a set of candidate PDCCHs. The search space mayinclude a common search space (common search space) and a UE-specificsearch space (UE-specific search space). The common search space is usedto transmit related control information such as a paging (Paging)message and system information. The UE-specific search space is used forcontrol information related to a downlink shared channel (downlinkshared channel. DL-SCH), an uplink shared channel (uplink sharedchannel. UL-SCH), and the like. Certainly, the common search space maybe also used to transmit control information belonging to specific UE.This is not limited in the embodiments of this application.

It may be understood that a network device may configure one or moresearch spaces for a terminal, or a network device may delete a searchspace previously configured for a terminal. For example, the followingshows corresponding signaling configured by the network device for theterminal in a current protocol.

 PDCCH-Config ::=  SEQUENCE {  ...  searchSpacesToAddModListSEQUENCE(SIZE (1..10)) OF SearchSpace OPTIONAL, -- Need N searchSpacesToReleaseList SEQUENCE(SIZE (1..10)) OF SearchSpaceIdOPTIONAL, --Need N  ...  }

Herein, searchSpacesToAddModList indicates a list of newly added searchspaces. SEQUENCE is used to indicate that the variablesearchSpacesToAddModList is of an array type (or referred to as a listtype). SIZE (1 . . . 10) means that the array (or list) includes 1 to 10elements. OF SearchSpace means that each element in the array (or list)is a variable of a type SearchSpace.

Herein, searchSpacesToReleaseList indicates a list of to-be-deletedsearch spaces. SEQUENCE is used to indicate that the variablesearchSpacesToReleaseList is of an array type (or referred to as a listtype). SIZE (1 . . . 10) means that the array (or list) includes 1 to 10elements. OF SearchSpaceId means that each element in the array (orlist) is a variable of a type SearchSpaceId.

OPTIONAL is used to indicate that a parameter is optional (optional) butnot mandatory (mandatory).

Need N is used to indicate that, once a parameter (for example,searchSpacesToAddModList or searchSpacesToReleaseList) does not exist ina reconfiguration message, a previously configured value of theparameter is erased, which means that the parameter has not beenconfigured.

For specific descriptions of the foregoing signaling, refer to theconventional technology. Details are not described herein.

5. Configuration Parameter of a Search Space

Optionally, the configuration parameter of the search space may be anaggregation level, a quantity of candidate PDCCHs corresponding to theaggregation level, a monitoring cycle, a monitoring offset value, a timedomain length, a to-be-monitored symbol in a slot, or a type of thesearch space.

For example, in a protocol, a SearchSpace information element(information element, IE) may be used to configure a configurationparameter of a search space. The SearchSpace IE may be as follows: Forspecific content of the information element, refer to relateddescriptions in the 3rd generation partnership project (3rd generationpartnership project, 3GPP) technical specification (technicalspecification, TS) 38.331.

 SearchSpace ::= SEQUENCE {  ...  monitoringSlotPeriodicityAndOffset  CHOICE {    sl1  NULL,    sl2  INTEGER (0..1),    sl4  INTEGER (0..3),   sl5  INTEGER (0..4),    sl8  INTEGER (0..7),    sl10  INTEGER (0..9),   sl16  INTEGER (0..15),    sl20  INTEGER (0..19),    sl40  INTEGER(0..39),    sl80  INTEGER (0..79),    sl160  INTEGER (0..159),    sl320 INTEGER (0..319),    Sl640  INTEGER (0..639),    sl1280  INTEGER(0..1279),    sl2560  INTEGER (0..2559)  } OPTIONAL, -- Cond Setup duration  INTEGER (2..2559) OPTIONAL, -- Need R monitoringSymbolsWithinSlot   BIT STRING (SIZE (14)) OPTIONAL, -- CondSetup  nrofCandidates   SEQUENCE {   aggregationLevel1  ENUMERATED {n0,n1, n2, n3, n4, n5, n6, n8},   aggregationLevel2  ENUMERATED {n0, n1,n2, n3, n4, n5, n6, n8},   aggregationLevel4  ENUMERATED {n0, n1, n2,n3, n4, n5, n6, n8},   aggregationLevel8  ENUMERATED {n0, n1, n2, n3,n4, n5, n6, n8},   aggregationLevel16  ENUMERATED {n0, n1, n2, n3, n4,n5, n6, n8}  } OPTIONAL, -- Cond Setup  searchSpaceType   CHOICE {  common  SEQUENCE {     dci-Format0-0-AndFormat1-0  SEQUENCE {      ...    }  OPTIONAL, -- Need R     dci-Format2-0 SEQUENCE {     nrofCandidates-SFI SEQUENCE { aggregationLevel1 ENUMERATED {n1, n2}OPTIONAL,-- Need R aggregationLevel2 ENUMERATED {n1, n2} OPTIONAL,--Need R aggregationLevel4 ENUMERATED {n1, n2} OPTIONAL,-- Need RaggregationLevel8 ENUMERATED {n1, n2} OPTIONAL,-- Need RaggregationLevel16 ENUMERATED {n1, n2} OPTIONAL -- Need R      },     ...     }  OPTIONAL,-- Need R     dci-Format2-1   SEQUENCE {     ...     }  OPTIONAL,-- Need R     dci-Format2-2   SEQUENCE {     ...     }  OPTIONAL,-- Need R     dci-Format2-3   SEQUENCE {     monitoringPeriodicityENUMERATED {n1, n2, n4, n5, n8, n10, n16, n20} OPTIONAL,  -- Cond Setup      nrofPDCCH-Candidates ENUMERATED {n1,n2},      ...     }  OPTIONAL -- Need R    },    ue-Specific SEQUENCE {    dci-Formats ENUMERATED {formats0-0-And-1-0, formats0-1-And- 1-1},    ...    }  }  }

The following briefly describes each configuration parameter of thesearch space with reference to the foregoing information element.

(1) monitoringSlotPeriodicityAndOffset is used to indicate a monitoringcycle and a monitoring offset value of the search space.

In the embodiments of this application, one monitoring cycle may includeat least one slot. In the foregoing information element, a networkdevice may select a parameter from sl1, sl2 . . . , and sl12560 toconfigure the monitoring cycle. Herein, sl1 indicates that onemonitoring cycle includes one slot, and sl2 indicates that onemonitoring cycle includes two slots. By analogy, sl12560 indicates thatone monitoring cycle includes 12560 slots.

INTEGER is used to indicate a monitoring offset value. The monitoringoffset value is used to determine a start slot in which a terminalperforms monitoring in the monitoring cycle. Specifically, themonitoring offset value is used to determine a slot, in the monitoringcycle, in which the terminal starts to monitor the search space. Forexample, if the monitoring cycle includes four slots, and the monitoringoffset value is 2, it indicates that the terminal starts to monitor thesearch space in a third slot in the monitoring cycle. It should be notedthat the monitoring offset value cannot be greater than a length of themonitoring cycle (that is, a quantity of slots included in themonitoring cycle). For example, the monitoring cycle is sl2, and INTEGER(0 . . . 1) is used to indicate that a value range of the monitoringoffset value is {0, 1}. The monitoring cycle is sl4, and INTEGER (0 . .. 3) is used to indicate that a value range of the monitoring offsetvalue is {0, 1, 2, 3}.

(2) duration is used to indicate a time domain length of the searchspace. The time domain length of the search space is a quantity of slotsthat last each time the search space appears, that is, a quantity ofslots in which a terminal needs to perform monitoring. For example, ifthe time domain length of the search space is three slots, the terminalneeds to monitor the search space in three consecutive slots.

(3) monitoringSymbolsWithinSlot is used to indicate a to-be-monitoredstart symbol in one slot. It should be noted that the symbol is anorthogonal frequency division multiplexing (orthogonal frequencydivision multiplexing, OFDM) symbol.

In specific implementation, monitoringSymbolsWithinSlot is a sequencewith a length of 14 bits. Each bit in the sequence of 14 bits is in aone-to-one correspondence with each OFDM symbol in the slot. A value ofeach bit in the sequence of 14 bits is used to indicate whether an OFDMsymbol corresponding to the bit is a start symbol. Specifically, when avalue of one bit in the sequence of 14 bits is 1, it indicates that anOFDM symbol corresponding to the bit is a start symbol. When a value ofone bit in the sequence of 14 bits is 0, it indicates that an OFDMsymbol corresponding to the bit is not a start symbol. For example, ifthe sequence of 14 bits is 1000000100000, a symbol #0 and a symbol #7 inthe slot are start symbols.

It should be noted that, if a cyclic prefix (cyclic prefix, CP) of asymbol is set to an extended (extended) cyclic prefix in a bandwidthpart (bandwidth part, BWP) configured by a network device fora terminal,the last two bits of monitoringSymbolsWithinSlot may be ignored.

It should be noted that the start symbol is the first symbol in aplurality of consecutive to-be-monitored symbols in one slot. One slotmay include a plurality of start symbols. The terminal may determine,based on a start symbol configured in monitoringSymbolsWithinSlot and aspecific quantity of consecutive to-be-monitored symbols configured in acontrol resource set (ControlResourceSet, CORESET), symbols that are tobe monitored symbols in one slot. For example, ifmonitoringSvmbolsWithinSlot is 1000000100000, and the specific quantityof consecutive to-be-monitored symbols configured in the controlresource set is 3, a symbol #0, a symbol #1, a symbol #2, a symbol #7, asymbol #8, and a symbol #9 in the slot are to-be-monitored symbols.

(4) nrofCandidates is used to configure a quantity of candidate PDCCHscorresponding to each of a plurality of aggregation levels of the searchspace.

The aggregation level is a quantity of CCEs included in one PDCCH. Aplurality of aggregation levels are defined in a protocol, for example,1, 2, 4, 8, and 16. For example, if the aggregation level of the searchspace is 16, it indicates that the PDCCH carried in the search spaceincludes 16 CCEs.

It should be noted that, unless otherwise specified, the quantity ofcandidate PDCCHs corresponding to each aggregation level of the searchspace that is configured by using nrofCandidates is applicable to anyDCI format.

(5) searchSpaceType is used to indicate a type of the search space, thatis, used to indicate whether the search space is a common search spaceor a UE-specific search space.

When searchSpaceType is set to common, it indicates that the searchspace is a common search space. In this case, searchSpaceType mayfurther include any one or more of the following parameters:dci-Format0-0-AndFormat1-0, dci-Format2-0, dci-Format2-1, dci-Format2-2,and dci-Format2-3. When any one of the foregoing parameters is selected,it indicates that a terminal needs to monitor, in the search space, aDCI format corresponding to the parameter. When one of the foregoingparameters is not selected, it indicates that the terminal does not needto monitor, in the search space, a DCI format corresponding to theparameter. For example, when searchSpaceType includesdci-Format0-0-AndFormat1-0, and does not include the other parameters,it indicates that the terminal needs to monitor a DCI format 0-0 and aDCI format 1-0, and does not need to monitor a DCI format 2-0, a DCIformat 2-1, a DCI format 2-2, and a DCI format 2-3 in the search space.

When searchSpaceType is set to UE-specific, it indicates that the searchspace is a UE-specific search space. In this case, searchSpaceType mayfurther include any one or more of the following parameters:formats0-0-And-1-0 and formats0-1-And-1-1. When any one of the foregoingparameters is selected, it indicates that the terminal needs to monitor,in the search space, a DCI format corresponding to the parameter. Whenone of the foregoing parameters is not selected, it indicates that theterminal does not need to monitor, in the search space, a DCI formatcorresponding to the parameter. If formats0-0-And-1-0 is configured insearchSpaceType but formats0-1-And-1-1 is not configured, the terminalneeds to monitor a DCI format 0-0 and a DCI format 1-0, and does notneed to monitor a DCI format 0-1 and a DCI format 1-1 in the searchspace.

6. DRX

A DRX mechanism includes two modes: idle (IDLE) DRX and connected(connected) DRX. The two types of DRX are implemented differently. Theembodiments of this application mainly describe the connected DRX(C-DRX).

The DRX mechanism configures one DRX cycle (cycle) for a terminal in RRCconnected mode. As shown in FIG. 1, the DRX cycle includes “on duration”and “opportunity for DRX”. Within a time of “on duration”, the terminalmonitors and receives a downlink control channel (for example, a PDCCH).Within a time of “opportunity for DRX”, the terminal does not receivedata from a downlink channel for power saving.

The DRX cycle may be classified into a long DRX cycle and a short DRXcycle. Generally, the long DRX cycle is an integer multiple of the shortDRX cycle. It should be noted that the long DRX cycle is mandatory bydefault, and the short DRX cycle is optional. To be specific, when theDRX mechanism is used, a network device needs to configure a long DRXcycle for a terminal, and the network device may or may not configure ashort DRX cycle for the terminal. Signaling used to configure a long DRXcycle or a short DRX cycle may be RRC signaling.

Optionally, RRC signaling used to configure a long DRX cycle includes atleast the following parameters: a time length of the long DRX cycle, atime length of on duration, and the like.

Optionally, RRC signaling used to configure a short DRX cycle includesat least the following parameters: a time length of the short DRX cycle,a time length of drx-ShortCycleTimer, and the like.

If the network device configures a short DRX cycle for the terminal, theterminal starts a timer drx-ShortCycleTimer when using the short DRXcycle. When the timer drx-ShortCycleTimer expires, the terminal switchesfrom using the short DRX cycle to using a long DRX cycle. A timinglength of the timer drx-ShortCycleTimer is generally an integer multipleof the short DRX cycle.

In addition, the network device may send media access control (mediaaccess control, MAC) control element (control element, CE) signaling tothe terminal, to indicate the terminal to switch between a long DRXcycle and a short DRX cycle.

In the embodiments of this application, that the terminal uses a longDRX cycle may be understood as: The terminal is using the long DRXcycle, or the terminal switches to a mode of the long DRX cycle. It maybe understood that when the terminal switches to a mode of the long DRXcycle, a first long DRX cycle may not actually start.

In the embodiments of this application, that the terminal uses a shortDRX cycle may be understood as: The terminal is using the short DRXcycle, or the terminal switches to the short DRX cycle. It may beunderstood that when the terminal switches to a mode of the short DRXcycle, a first short DRX cycle may not actually start.

7. DRX cycle associated with a power saving signal, and power savingsignal associated with a DRX cycle

The DRX cycle associated with the power saving signal is a DRX cycle ofterminal behavior indicated by the power saving signal.

The power saving signal associated with the DRX cycle is a power savingsignal indicating terminal behavior in the DRX cycle.

Generally, the power saving signal is sent in several slots or severalmilliseconds before the DRX cycle associated with the power savingsignal. For example, if a terminal receives a power saving signal #1 inN slots or M milliseconds before a DRX cycle #1, a DRX cycle associatedwith the power saving signal #1 is a DRX cycle #1, and a power savingsignal associated with the DRX cycle #1 is the power saving signal #1.

The terminal behavior may be: whether the terminal detects a PDCCH,whether the terminal switches between BWPs, whether the terminalperforms channel state measurement and reporting, and the like.

The following describes use of a long DRX cycle and a short DRX cycle inan actual application scenario by using an example. For example, when auser uses a mobile phone to watch a video, the mobile phone may use ashort DRX cycle, and a length of the short DRX cycle may be 40 ms, thatis, the mobile phone monitors, every 40 ms (that is, on duration of theshort DRX cycle), scheduling information sent by a base station. Afterreceiving the scheduling information, the mobile phone determines, basedon the scheduling information sent by the base station, a time-frequencyresource location at which the video data is received, and obtains thevideo data at the corresponding time-frequency resource location. If themobile phone has finished buffering the video data and does not need toreceive the video data temporarily, the mobile phone does not receive,within a period of time (for example, several short DRX cycles),scheduling information sent by the base station. Once a time in whichthe mobile phone does not receive scheduling information exceeds apreset threshold, the mobile phone may switch from using the short DRXcycle to using a long DRX cycle. A length of the long DRX cycle used bythe mobile phone may be 160 ms. In this way, the mobile phone monitors,every 160 ms, scheduling information sent by the base station. Comparedwith the short DRX cycle used by the mobile phone, the long DRX cycleused by the mobile phone may increase a sleep time of the mobile phone,thereby helping reduce power consumption of the mobile phone.

The foregoing briefly describes the terms in the embodiments of thisapplication. Details are not described below again.

Currently, a monitoring cycle of a search space is fixed. Therefore, ifa network device configures only one search space used to carry a powersaving signal for a terminal, the search space cannot be applied to botha long DRX cycle and a short DRX cycle. For example, it is assumed thatthe monitoring cycle of the search space is the same as the long DRXcycle. Generally, the long DRX cycle is an integer multiple of the shortDRX cycle. Therefore, the monitoring cycle of the search space is aninteger multiple of the short DRX cycle. Therefore, when the terminaluses the short DRX cycle, a monitoring occasion of the search space maynot exist in the short DRX cycle, and consequently the terminal missesdetecting a power saving signal in the short DRX cycle.

As shown in FIG. 2, the monitoring cycle of the search space is the sameas the long DRX cycle, and a cycle length of the long DRX cycle is twicea cycle length of the short DRX cycle. It can be learned that, in thiscase, when the terminal switches from using the long DRX cycle to usingthe short DRX cycle, a monitoring occasion does not exist in the searchspace in a first short DRX cycle. Consequently, the terminal cannotnormally monitor a power saving signal in the short DRX cycle.

Alternatively, the network device configures two search spaces used tocarry a power saving signal for the terminal, where a monitoring cycleof one search space matches a long DRX cycle, and a monitoring cycle ofthe other search space matches a short DRX cycle. However, according tothe conventional technology, once a network side configures two searchspaces for a terminal, the terminal monitors the two search spacesregardless of whether the terminal uses a long DRX cycle or a short DRXcycle. However, the power saving signal is used to indicate that theterminal is in a sleep state or a normal working state in on duration ofa DRX cycle associated with the power saving signal, and the powersaving signal needs to be transmitted only in a search spacecorresponding to a DRX cycle currently used by the terminal. Forexample, the cycle length of the long DRX cycle is twice the cyclelength of the short DRX cycle in FIG. 2. When the terminal uses the longDRX cycle, before on duration of the long DRX cycle, in addition tomonitoring a search space corresponding to the long DRX cycle once, theterminal further needs to monitor a search space corresponding to theshort DRX cycle twice. However, the power saving signal needs to betransmitted only in the search space corresponding to the long DRXcycle, and consequently the terminal cannot receive the power savingsignal even if the terminal monitors the search space corresponding tothe short DRX cycle. Similarly, when the terminal uses the short DRXcycle, before on duration of the short DRX cycle, in addition tomonitoring a search space corresponding to the short DRX cycle, theterminal further needs to monitor a search space corresponding to thelong DRX cycle. However, the power saving signal needs to be transmittedonly in the search space corresponding to the short DRX cycle, andconsequently the terminal cannot receive the power saving signal even ifthe terminal monitors the search space corresponding to the long DRXcycle. Consequently, power consumption of the terminal is increased.

To resolve the foregoing technical problem, the embodiments of thisapplication provide the following technical solutions. For specificcontent, refer to the following content.

The technical solutions provided in the embodiments of this applicationmay be applied to various communications systems, for example, a newradio (new radio, NR) communications system using a fifth generation(5th generation, 5G) communications technology, a future evolved system,or a plurality of convergent communications systems. The technicalsolutions provided in this application may be applied to a plurality ofapplication scenarios, for example, machine to machine (machine tomachine, M2M), macro-micro communication, enhanced mobile broadband(enhanced mobile broadband, eMBB), ultra-reliable low-latencycommunication (ultra reliable & low latency communication, uRLLC), andmassive machine-type communications (massive machine type communication,mMTC). These scenarios may include but are not limited to a scenario ofcommunication between communications devices, a scenario ofcommunication between network devices, a scenario of communicationbetween a network device and a communications device, and the like. Thefollowing provides descriptions by using an example in which thetechnical solutions are applied to a scenario of communication between anetwork device and a terminal.

In addition, a network architecture and a service scenario described inthe embodiments of this application are intended to describe thetechnical solutions in the embodiments of this application more clearly,and do not constitute a limitation on the technical solutions providedin the embodiments of this application. A person of ordinary skill inthe art may know that, with evolution of the network architecture andemergence of a new service scenario, the technical solutions provided inthe embodiments of this application are also applicable to similartechnical problems.

FIG. 3 is a schematic diagram of an architecture of a communicationssystem to which the technical solutions provided in this application areapplicable. The communications system may include one or more networkdevices (FIG. 3 shows only one network device) and one or more terminals(FIG. 3 shows only one terminal).

The network device may be a base station, a base station controller, orthe like in wireless communication. The base station may include varioustypes of base stations, such as a micro base station (also referred toas a small cell), a macro base station, a relay node, and an accesspoint. This is not specifically limited in the embodiments of thisapplication. In the embodiments of this application, the base stationmay be a base transceiver station (base transceiver station, BTS) in aglobal system for mobile communications (global system for mobilecommunications, GSM) or code division multiple access (code divisionmultiple access, CDMA), a NodeB (NodeB) in wideband code divisionmultiple access (wideband code division multiple access, WCDMA), anevolved NodeB (evolved NodeB, eNB or e-NodeB) in long term evolution(long term evolution, LTE), an eNB in the internet of things (internetof things, IoT) or the narrowband internet of things (narrowbandinternet of things, NB-IoT), or a base station in a future 5G mobilecommunications network or a future evolved public land mobile network(public land mobile network, PLMN). This is not limited in theembodiments of this application. In the embodiments of this application,an apparatus configured to implement a function of the network devicemay be a network device, or may be an apparatus that can support thenetwork device in implementing the function, for example, a chip system.In the embodiments of this application, an example in which an apparatusconfigured to implement a function of the network device is a networkdevice is used to describe the technical solutions provided in theembodiments of this application.

A network device described in this application, for example, a basestation, usually includes a baseband unit (baseband unit, BBU), a remoteradio unit (remote radio unit, RRU), an antenna, and a feeder used toconnect the RRU and the antenna. The BBU is configured to be responsiblefor signal modulation. The RRU is configured to be responsible for radiofrequency processing. The antenna is configured to be responsible forconversion between a pilot wave on a cable and a space wave in the air.On one hand, a distributed base station greatly shortens a length of thefeeder between the RRU and the antenna, thereby reducing a signal loss,and reducing costs of the feeder. On the other hand, the RRU and theantenna are relatively small and can be installed anywhere, makingnetwork planning more flexible. The RRU may be remotely placed. Inaddition to that, all BBUs may be centralized and placed in a centraloffice (central office, CO). In this centralized manner, a quantity ofbase station equipment rooms can be greatly reduced, energy consumptionof auxiliary devices, especially air conditioners, can be reduced, andcarbon emissions can be greatly reduced. In addition, after distributedBBUs are integrated into a BBU baseband pool, the BBUs can be managedand scheduled centrally, and resources can be allocated more flexibly.In this mode, all physical base stations evolve into virtual basestations. All the virtual base stations share information such as datasent and received by users and channel quality in the BBU baseband pool,and cooperate with each other, to implement joint scheduling.

In some deployments, the base station may include a centralized unit(centralized unit, CU) and a distributed unit (Distributed Unit, DU).The base station may further include an active antenna unit (activeantenna unit, AAU). The CU implements some functions of the basestation, and the DU implements some functions of the base station. Forexample, the CU is responsible for processing a non-real-time protocoland service, and implements functions of a radio resource control (radioresource control, RRC) layer and a packet data convergence protocol(packet data convergence protocol, PDCP) layer. The DU is responsiblefor processing a physical layer protocol and a real-time service, andimplements functions of a radio link control (radio link control, RLC)layer, a media access control (media access control, MAC) layer, and aphysical (physical, PHY) layer. The AAU implements some physical layerprocessing functions, radio frequency processing, and a function relatedto an active antenna. Information at the RRC layer eventually becomesinformation at the PHY layer, or is converted from the information atthe PHY layer. Therefore, in this architecture, higher layer signaling,for example, RRC layer signaling or PDCP layer signaling, may also beconsidered as being sent by the DU or sent by the DU and the AAU. It maybe understood that the network device may be a device including one ormore of a CU node, a DU node, and an AAU node. In addition, the CU maybe classified as a network device in the RAN, or the CU may beclassified as a network device in a core network (core network, CN).This is not limited herein.

The terminal is a device that has a wireless transceiver function. Theterminal may be deployed on land, including an indoor device, an outdoordevice, a handheld device, or a vehicle-mounted device, may be deployedon a water surface (such as on a ship), or may be deployed in the air(for example, on an aircraft, a balloon, or a satellite). The terminaldevice may be user equipment (user equipment, UE). The UE includes ahandheld device, a vehicle, a vehicle-mounted device, a wearable device,or a computing device that has a wireless communication function. Forexample, the UE may be a mobile phone (mobile phone), a tablet computer,or a computer having a wireless transceiver function. Alternatively, theterminal device may be a virtual reality (virtual reality, VR) terminaldevice, an augmented reality (augmented reality, AR) terminal device, awireless terminal in industrial control, a wireless terminal inself-driving, a wireless terminal in telemedicine, a wireless terminalin a smart grid, a wireless terminal in a smart city (smart city), awireless terminal in a smart home (smart home), or the like. In theembodiments of this application, an apparatus configured to implement afunction of the terminal may be a terminal, or may be an apparatus thatcan support the terminal in implementing the function, for example, achip system. In the embodiments of this application, the chip system mayinclude a chip, or may include a chip and another discrete component. Inthe embodiments of this application, an example in which an apparatusconfigured to implement a function of the terminal is a terminal is usedto describe the technical solutions provided in the embodiments of thisapplication.

As shown in FIG. 4, the communications apparatus includes at least oneprocessor 101, a communications line 102, a memory 103, and at least onecommunications interface 104.

The processor 101 may be a general-purpose central processing unit(central processing unit, CPU), a microprocessor, anapplication-specific integrated circuit (application-specific integratedcircuit, ASIC), or one or more integrated circuits configured to controlprogram execution of the solutions of this application.

The communications line 102 may include a path for transferringinformation between the components described above.

The communications interface 104, which uses any apparatus such as atransceiver, is configured to communicate with another device orcommunications network, such as the Ethernet, a RAN, or a wireless localarea network (wireless local area networks, WLAN).

The memory 103 may be a read-only memory (read-only memory. ROM) oranother type of static storage device capable of storing staticinformation and instructions, or a random access memory (random accessmemory. RAM) or another type of dynamic storage device capable ofstoring information and instructions. Alternatively, the memory 103 maybe an electrically erasable programmable read-only memory (electricallyerasable programmable read-only memory, EEPROM), a compact discread-only memory (compact disc read-only memory, CD-ROM) or anotheroptical disk storage, an optical disc storage (including a compactoptical disc, a laser disc, an optical disc, a digital versatile disc, aBlu-ray disc, or the like), a magnetic disk storage medium or anothermagnetic storage device, or any other medium that can be configured tocarry or store expected program code in a form of instructions or a datastructure and that can be accessed by a computer. However, this is notlimited herein. The memory may exist independently, and is connected tothe processor through the communications line 102. The memory mayalternatively be integrated with the processor. The memory provided inthis embodiment of this application may usually be non-volatile. Thememory 103 is configured to store computer-executable instructions forperforming the solutions of this application, and the processor 101controls execution of the computer-executable instructions. Theprocessor 101 is configured to execute the computer-executableinstructions stored in the memory 103, to implement the method providedin the embodiments of this application.

Optionally, the computer-executable instructions in the embodiments ofthis application may also be referred to as application program code.This is not specifically limited in the embodiments of this application.

In specific implementation, in an embodiment, the processor 101 mayinclude one or more CPUs such as a CPU 0 and a CPU 1 in FIG. 4.

In specific implementation, in an embodiment, the communicationsapparatus may include a plurality of processors, for example, theprocessor 101 and a processor 107 in FIG. 4. Each of the processors maybe a single-core (single-CPU) processor, or may be a multi-core(multi-CPU) processor. The processor herein may be one or more devices,circuits, and/or processing cores configured to process data (forexample, computer program instructions).

In specific implementation, in an embodiment, the communicationsapparatus may further include an output device 105 and an input device106. The output device 105 communicates with the processor 101, and maydisplay information in a plurality of manners. For example, the outputdevice 105 may be a liquid crystal display (liquid crystal display,LCD), a light emitting diode (light emitting diode, LED) display device,a cathode ray tube (cathode ray tube, CRT) display device, or aprojector (projector). The input device 106 communicates with theprocessor 101, and may receive an input from a user in a plurality ofmanners. For example, the input device 106 may be a mouse, a keyboard, atouchscreen device, or a sensor device.

The following describes the technical solutions provided in theembodiments of this application in detail with reference to theaccompanying drawings of this specification.

FIG. 5 shows a search space monitoring method according to an embodimentof this application. The method includes the following steps.

S101: When a terminal uses a long DRX cycle, a network device sends apower saving signal in a first search space, and does not send the powersaving signal in a second search space.

Optionally, step S101 may be expressed as follows: The network devicesends, in the first search space, the power saving signal associatedwith the long DRX cycle, and does not send, in the second search space,the power saving signal associated with the long DRX cycle.

The first search space and the second search space are two differentsearch spaces. The first search space and the second search space aresearch spaces that are configured by the network device and that areused to carry the power saving signal. The first search spacecorresponds to a long DRX cycle, and the second search space correspondsto a short DRX cycle.

Optionally, the network device may explicitly enable the terminal tolearn a search space used to carry the power saving signal. For example,the network device may send first information to the terminal, and thefirst information includes identifiers of one or more search spaces usedto carry the power saving signal.

Optionally, the network device may implicitly enable the terminal tolearn a search space used to carry the power saving signal. For example,the network device may send configuration information of the searchspace to the terminal. If the configuration information of the searchspace includes a DCI format corresponding to the power saving signal,the search space is a search space used to carry the power savingsignal.

In this embodiment of this application, the power saving signal is usedto indicate power saving information. Optionally, the power savinginformation includes at least one of the following:

(1) Whether the terminal monitors a PDCCH in a DRX cycle associated withthe power saving signal: The power saving signal may be used to indicatethe terminal to monitor the PDCCH in the DRX cycle associated with thepower saving signal. Alternatively, the power saving signal may be usedto indicate the terminal not to monitor the PDCCH in the DRX cycleassociated with the power saving signal. “Whether to monitor the PDCCHin the DRX cycle” may also be equivalently expressed as “whether tomonitor the PDCCH in on duration of DRX”.

It may be understood that, when the power saving signal is used toindicate the terminal not to monitor the PDCCH in the DRX cycleassociated with the power saving signal, the terminal does not monitorthe PDCCH, thereby reducing power consumption of the terminal. The PDCCHherein includes at least a PDCCH used to schedule uplink data: a PUSCHor downlink data: a PDSCH, that is, a PDCCH carrying a DCI format 0-0, aDCI format 0-1, a DCI format 1-0, and a DCI format 1-1. The PDCCH mayfurther include a PDCCH with another function, for example, a PDCCHcarrying a DCI format 2-0 and/or a DCI format 2-1 and/or a DCI format2-2 and/or a DCI format 2-3.

(2) Minimum scheduling time interval indication; The minimum schedulingtime interval indication may be a minimum K0 value or a minimum K2value. K0 is a time interval between a slot in which a PDCCH is locatedand a slot in which a PDSCH scheduled by using the PDCCH is located. K2is a time interval between a slot in which a PDCCH is located and a slotin which a PDSCH scheduled by using the PDCCH is located.

(3) Channel state information (channel state information, CSI)measurement trigger indication: The CSI measurement trigger indicationis used to trigger the terminal to perform CSI-RS measurement and CSIreporting.

(4) Bandwidth part (bandwidth part, BWP) switching indication: The BWPswitching indication is used to indicate the terminal to switch betweenBWPs. In other words, the BWP switching indication is used to indicatethe terminal to switch from a first BWP to a second BWP.

It may be understood that the first BWP is a BWP used by the terminalbefore the switching, and the second BWP is a BWP used by the terminalafter the switching. The second BWP may be preconfigured, or may bedetermined by the terminal based on the BWP switching indication. Thisis not limited in this embodiment of this application.

(5) Search space and/or control resource set (control resource set,CORESET) that the terminal needs to monitor in the DRX cycle associatedwith the power saving signal

For example, the network device configures a search space #1, a searchspace #1, and a search space #3 for the terminal, and the power savingsignal may indicate that the terminal needs to monitor the search space#1 and the search space #3.

For example, the network device configures a CORESET #1, a CORESET #2,and a CORESET #3 for the terminal, and the power saving signal mayindicate that the terminal needs to monitor the CORESET #1.

It may be understood that, for a plurality of search spaces and/orCORESETs configured by the network device for the terminal, the powersaving signal may indicate the terminal to monitor only some of thesearch spaces and/or CORESETs, so as to reduce a quantity of searchspaces and/or CORESETs that the terminal needs to monitor, therebyreducing power consumption of the terminal.

(6) Monitoring cycle in which the terminal monitors the PDCCH in the DRXcycle associated with the power saving signal

(7) Skipping duration (skipping duration) used by the terminal in theDRX cycle associated with the power saving signal: The skipping durationis duration in which the terminal skips monitoring the PDCCH. Theskipping duration may include monitoring occasions of one or moreslots/subframes/PDCCHs. This is not limited in this embodiment of thisapplication.

The foregoing is an example of the power saving information, and thisembodiment of this application is not limited thereto.

Optionally, the power saving signal may include one or more informationelements, and one information element is used to carry one piece ofpower saving information. In this way, the power saving signal mayindicate a plurality of pieces of power saving informationsimultaneously.

Optionally, the power saving signal includes an index, and the index maybe implemented by using one or more bits. Power saving informationindicated by using the power saving signal varies with a value of theindex included in the power saving signal. That is, the value of theindex corresponds to one or more pieces of power saving information.

For example, Table 1 shows a correspondence between a value of an indexand power saving information. For example, with reference to Table 1,when the value of the index included in the power saving signal is 00,the power saving signal is used to indicate the terminal to monitor thePDCCH. When the value of the index included in the power saving signalis 01, the power saving signal is used to indicate the terminal not tomonitor the PDCCH. When the value of the index included in the powersaving signal is 10, the power saving signal is used to indicate theterminal to switch between BWPs. When the value of the index included inthe power saving signal is 11, the power saving signal is used toindicate the terminal not to monitor the PDCCH but to switch betweenBWPs.

TABLE 1 Value of the index Power saving information 00 Monitor the PDCCH01 Not to monitor the PDCCH 10 Switch between BWPs 11 Not to monitor thePDCCH but switch between BWPs

S102: When using the long DRX cycle, the terminal monitors the powersaving signal in the first search space, and does not monitor the powersaving signal in the second search space.

Optionally, step S102 may also be expressed as follows: The terminalmonitors, in the first search space, the power saving signal associatedwith the long DRX cycle, and does not monitor, in the second searchspace, the power saving signal associated with the short DRX cycle.

Optionally, the terminal may implicitly determine the first search spaceand the second search space. For example, when the network deviceconfigures two search spaces used to carry a power saving signal for theterminal, the terminal may determine the first search space and thesecond search space based on monitoring cycles of the two search spaces.For example, a search space with a longer monitoring cycle in the twosearch spaces is used as the first search space, and a search space witha shorter monitoring cycle in the two search spaces is used as thesecond search space. Alternatively, a search space with a samemonitoring cycle as the long DRX cycle is used as the first searchspace, and a search space with a same monitoring cycle as the short DRXcycle is used as the second search space.

Optionally, the terminal may explicitly determine the first search spaceand the second search space. For example, the terminal receives firstconfiguration information sent by the network device, and the firstconfiguration information is used to configure related information ofthe power saving signal. The first configuration information includesfirst indication information and second indication information, thefirst indication information is used to indicate an identifier/an indexvalue/a name of the first search space, and the second indicationinformation is used to indicate an identifier/an index value/a name ofthe second search space. In this way, the terminal may determine thefirst search space based on the first indication information, anddetermine the second search space based on the second indicationinformation. For example, the first indication information isSearchSpaceIdForLongCycle, and is used to indicate an identifier/anindex value/a name of a search space that needs to be monitored when theterminal uses the long DRX cycle, and the second indication informationis SearchSpaceIdForShortCycle, and is used to indicate an identifier/anindex value/a name of a search space that needs to be monitored when theterminal uses the short DRX cycle.

Optionally, the first configuration information may further include afirst radio network temporary identifier (radio network temporaryidentifier, RNTI), and the first RNTI is used to identify the terminalthat receives the power saving signal. In this way, after the terminallearns of the first RNTI of the terminal, the terminal may determine,based on the first RNTI of the terminal, a power saving signal that issent to the terminal, so as to avoid incorrectly receiving a powersaving signal sent to another terminal. It may be understood that thefirst RNTI may have another name, for example, a power saving RNTI(power saving RNTI, PS-RNTI). This is not limited in this embodiment ofthis application.

In this embodiment of this application, a monitoring cycle of the firstsearch space may be the same as the long DRX cycle in terms of a timelength, and a monitoring cycle of the second search space may be thesame as the short DRX cycle in terms of a time length. In this way, amonitoring occasion of the first search space and a monitoring occasionof the second search space can occur at proper locations of the DRXcycle (for example, before on duration of the DRX cycle), and theterminal can normally monitor the power saving signal in the firstsearch space/the second search space.

Certainly, a monitoring cycle of the first search space mayalternatively be different from the long DRX cycle in terms of a timelength, and a monitoring cycle of the second search space mayalternatively be different from the short DRX cycle in terms of a timelength. This embodiment of this application is not limited thereto.

In this embodiment of this application, a monitoring offset value of thefirst search space may be the same as a monitoring offset value of thesecond search space. Alternatively, a monitoring offset value of thefirst search space may be different from a monitoring offset value ofthe second search space.

It should be noted that, when the terminal uses the long DRX cycle, thenetwork device may determine, based on an actual requirement, whether tosend the power saving signal in the first search space. However,regardless of whether the network device sends the power saving signal,the terminal needs to monitor the power saving signal in the firstsearch space.

S103: When the terminal uses a short DRX cycle, the network device sendsa power saving signal in a second search space, and does not send thepower saving signal in a first search space.

Optionally, step S103 may be expressed as follows: The network devicesends, in the second search space, the power saving signal associatedwith the short DRX cycle, and does not send, in the first search space,the power saving signal associated with the short DRX cycle.

S104: When using the short DRX cycle, the terminal monitors the powersaving signal in the second search space, and does not monitor the powersaving signal in the first search space.

Optionally, step S104 may also be expressed as follows. The terminalmonitors, in the second search space, the power saving signal associatedwith the short DRX cycle, and does not monitor, in the first searchspace, the power saving signal associated with the short DRX cycle.

It should be noted that, when the terminal uses the short DRX cycle, thenetwork device may determine, based on an actual requirement, whether tosend the power saving signal in the second search space. However,regardless of whether the network device sends the power saving signal,the terminal needs to monitor the power saving signal in the secondsearch space.

Based on the technical solution shown in FIG. 5, when the terminal usesthe long DRX cycle, the terminal monitors the power saving signal in thefirst search space, and does not monitor the power saving signal in thesecond search space. When the terminal uses the short DRX cycle, theterminal monitors the power saving signal in the second search space,and does not monitor the power saving signal in the first search space.In this way, the terminal can normally monitor the power saving signalin the search space in a scenario in which the power saving signal canbe applied to the long DRX cycle and the short DRX cycle. In addition,regardless of the long DRX cycle or the short DRX cycle, the terminalneeds to monitor the power saving signal in only one search space, sothat a quantity of search spaces that the terminal needs to monitor isreduced, and power consumption of the terminal is reduced.

The embodiment shown in FIG. 5 is described below by using an examplewith reference to FIG. 6.

The terminal enters a mode of the long DRX cycle before a long DRX cycle#1. Therefore, the network device sends a power saving signal in thefirst search space on a monitoring occasion #1 and a monitoring occasion#2 of the first search space. Correspondingly, the terminal monitors thepower saving signal in the first search space on the monitoring occasion#1 and the monitoring occasion #2 of the first search space. Theterminal enters a mode of the short DRX cycle before a short DRX cycle#1. Therefore, the network device sends a power saving signal on amonitoring occasion #1, a monitoring occasion #2, a monitoring occasion#3, and a monitoring occasion #4 of the second search space.Correspondingly, the terminal monitors the power saving signal on themonitoring occasion #1, the monitoring occasion #2, the monitoringoccasion #3, and the monitoring occasion #4 of the second search space.

In other words, the first search space is used to carry a power savingsignal associated with the long DRX cycle, and the second search spaceis used to carry a power saving signal associated with the short DRXcycle. Therefore, the long DRX cycle #1 is used as an example. Thenetwork device sends, in the first search space on the monitoringoccasion #1 of the first search space, a power saving signal associatedwith the long DRX cycle #1. Correspondingly, the terminal monitors, inthe first search space on the monitoring occasion #1 of the first searchspace, the power saving signal associated with the long DRX cycle #1.The short DRX cycle #1 is used as an example. The network device sends,in the second search space on the monitoring occasion #1 of the secondsearch space, a power saving signal associated with the short DRX cycle#1. Correspondingly, the terminal monitors, in the second search spaceon the monitoring occasion #1 of the second search space, the powersaving signal associated with the short DRX cycle #1.

The following describes the technical solutions of this application withreference to embodiments of some actual application scenarios.

For example, with reference to FIG. 7, when a user uses a mobile phoneto watch an online video, a requirement on a service delay is relativelylow. In this case, the mobile phone may use a long DRX cycle, and alength of the long DRX cycle may be 640 ms, that is, the mobile phonemonitors, every 640 ms (that is, on duration of the short DRX cycle),scheduling information sent by a base station. If the mobile phone hasfinished buffering the video data and does not need to receive the videodata temporarily, the mobile phone does not need to receive, within aperiod of time (for example, several long DRX cycles), schedulinginformation sent by the base station. In this case, the base station maysend a power saving signal to the mobile phone, to indicate that themobile phone may not monitor scheduling information in one or more longDRX cycles. Specifically, the base station may send a power savingsignal in the first search space, and does not send the power savingsignal in the second search space. Correspondingly, the mobile phone maymonitor the power saving signal in the first search space, and does notmonitor the power saving signal in the second search space.

For example, with reference to FIG. 8, when a user uses a mobile phoneto play an online game, a requirement on a service delay is relativelyhigh. In this case, the mobile phone may use a short DRX cycle, and alength of the short DRX cycle may be 40 ms, that is, the mobile phonemonitors, every 40 ms (that is, on duration of the short DRX cycle),scheduling information sent by a base station. In a game loadingprocess, the mobile phone does not need to perform data interaction withthe base station temporarily. In this case, the base station may send apower saving signal to the mobile phone, to indicate that the mobilephone may not monitor scheduling information in one or more short DRXcycles. Specifically, the base station may send a power saving signal inthe second search space, and does not send the power saving signal inthe first search space. Correspondingly, the mobile phone may monitorthe power saving signal in the second search space, and does not monitorthe power saving signal in the first search space.

FIG. 9 shows another search space monitoring method according to anembodiment of this application. The method includes the following steps.

S201: When a terminal uses a long DRX cycle, a network device sends apower saving signal in a search space based on a first group ofconfiguration parameters of the search space.

Optionally, step S201 may be expressed as follows: The network devicesends, in the search space based on the first group of configurationparameters of the search space, the power saving signal associated withthe long DRX cycle.

For related descriptions of the power saving signal, refer to thedescriptions in the embodiment shown in FIG. 5. Details are notdescribed herein again.

In this embodiment of this application, the first group of configurationparameters corresponds to the long DRX cycle. A monitoring cycle in thefirst group of configuration parameters may be the same as the long DRXcycle in terms of a time length. Alternatively, a monitoring cycle inthe first group of configuration parameters may be different from thelong DRX cycle in terms of a time length.

The search space is a search space used to carry the power savingsignal. For a method for configuring, by the network device, the searchspace used to carry the power saving signal for the terminal, refer torelated descriptions in the embodiment shown in FIG. 5. Details are notdescribed herein again.

S202: When using the long DRX cycle, the terminal monitors the powersaving signal in the search space based on the first group ofconfiguration parameters of the search space.

Optionally, step S202 may be expressed as follows: The terminalmonitors, in the search space based on the first group of configurationparameters of the search space, the power saving signal associated withthe long DRX cycle.

It should be noted that, when the terminal uses the long DRX cycle, thenetwork device may determine, based on an actual requirement, whether tosend the power saving signal in the search space. However, regardless ofwhether the network device sends the power saving signal, the terminalneeds to monitor the power saving signal in the search space based onthe first group of configuration parameters of the search space.

S203: When the terminal uses a short DRX cycle, the network device sendsa power saving signal in a search space based on a second group ofconfiguration parameters of the search space.

Optionally, step S203 may be expressed as follows: The network devicesends, in the search space based on the second group of configurationparameters of the search space, the power saving signal associated withthe short DRX cycle.

In this embodiment of this application, the second group ofconfiguration parameters corresponds to the short DRX cycle. Amonitoring cycle in the second group of configuration parameters may bethe same as the short DRX cycle in terms of a time length.Alternatively, a monitoring cycle in the second group of configurationparameters may be different from the short DRX cycle in terms of a timelength.

It should be noted that the first group of configuration parameters isdifferent from the second group of configuration parameters. That thefirst group of configuration parameters is different from the secondgroup of configuration parameters specifically means that the firstgroup of configuration parameters is different from the second group ofconfiguration parameters in at least one configuration parameter. Forexample, a monitoring cycle in the first group of configurationparameters is different from a monitoring cycle in the second group ofconfiguration parameters.

Optionally, a monitoring offset value in the first group ofconfiguration parameters is different from a monitoring offset value inthe second group of configuration parameters. Alternatively, amonitoring offset value in the first group of configuration parametersis the same as a monitoring offset value in the second group ofconfiguration parameters.

Optionally, the first group of configuration parameters and the secondgroup of configuration parameters are configured in at least thefollowing two manners:

Manner 1: The network device sends configuration information of thesearch space to the terminal, so that the terminal receives theconfiguration information of the search space that is sent by thenetwork device. The configuration information of the search spaceincludes the first group of configuration parameters and the secondgroup of configuration parameters.

For example, the configuration information of the search space may beimplemented in the following format, to configure the monitoring cycleand the monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

SearchSpace ::= SEQUENCE { ...monitoringSlotPeriodicityAndOffsetForLongDRX  CHOICE {  sl1  NULL,  sl2 INTEGER (0..1),  sl4  INTEGER (0..3),  sl5  INTEGER (0..4),  sl8 INTEGER (0..7),  sl10  INTEGER (0..9),  sl16  INTEGER (0..15),  sl20 INTEGER (0..19),  sl40  INTEGER (0..39),  sl80  INTEGER (0..79),  sl160 INTEGER (0..159),  sl320  INTEGER (0..319),  sl640  INTEGER (0..639), sl1280  INTEGER (0..1279),  sl2560  INTEGER (0..2559) } OPTIONAL, --Cond Setup monitoringSlotPeriodicityAndOffsetForShortDRX   CHOICE {  sl1 NULL,  sl2  INTEGER (0..1),  sl4  INTEGER (0..3),  sl5  INTEGER (0..4), sl8  INTEGER (0..7),  sl10  INTEGER (0..9),  Sl16  INTEGER (0..15), sl20  INTEGER (0..19),  sl40  INTEGER (0..39),  sl80  INTEGER (0..79), sl160  INTEGER (0..159),  sl320  INTEGER (0..319),  sl640  INTEGER(0..639),  sl1280  INTEGER (0..1279),  sl2560  INTEGER (0..2559) }OPTIONAL, -- Cond Setup ... }  OPTIONAL, -- Cond Setup

Herein, monitoringSlotPeriodicityAndOffsetForLongDRX is used to indicatea monitoring cycle and a monitoring offset value that correspond to thelong DRX cycle, that is, indicate the monitoring cycle and themonitoring offset value in the first group of configuration parameters.

monitoringSlotPeriodicityAndOffsetForShortDRX is used to indicate amonitoring cycle and a monitoring offset value that correspond to theshort DRX cycle, that is, indicate the monitoring cycle and themonitoring offset value in the second group of configuration parameters.

Cond Setup is used to indicate that a parameter corresponding to CondSetup is mandatory when a new search space is created. In other cases,the parameter corresponding to Cond Setup is optional. In addition, theparameter corresponding to Cond Setup needs to be retained after beingconfigured.

The parameter corresponding to Cond Setup may bemonitoringSlotPeriodicityAndOffsetForLongDRX andmonitoringSlotPeriodicityAndOffsetForShortDRX.

It should be noted that, when a target configuration parameter in thefirst group of configuration parameters is the same as a targetconfiguration parameter in the second group of configuration parameters,the configuration information of the search space may include only onetarget configuration parameter, thereby reducing signaling overheads ofthe configuration information of the search space. In this case, thetarget configuration parameter included in the configuration informationof the search space is applicable to the first group of configurationparameters and the second group of configuration parameters.

The target configuration parameter may be any configuration parameter ofthe search space, for example, a time domain length of the search spaceor a type of the search space. This is not limited in this embodiment ofthis application.

Manner 2: The network device sends configuration information of thesearch space to the terminal, so that the terminal receives theconfiguration information of the search space that is sent by thenetwork device. In addition, the network device sends indicationinformation to the terminal, so that the terminal receives theindication information sent by the network device.

The configuration information of the search space is used to indicate aparameter other than a monitoring cycle and a monitoring offset value inthe first group of configuration parameters, and a parameter other thana monitoring cycle and a monitoring offset value in the second group ofconfiguration parameter.

The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters. The indication informationincludes monitoringSlotPeriodicityAndOffsetForLongDRX andmonitoringSlotPeriodicityAndOffsetForShortDRX. Optionally, theindication information may be carried in configuration information ofthe power saving signal (that is, the first configuration informationmentioned above).

It may be understood that, in this case, when the configurationinformation of the search space uses SearchSpace IE, SearchSpace IE doesnot include monitoringSlotPeriodicityAndOffset, ormonitoringSlotPeriodicityAndOffset included in SearchSpace IE is notread by the terminal. In other words, the terminal does not determinethe monitoring cycle and the monitoring offset value of the search spacebased on monitoringSlotPeriodicityAndOffset included in SearchSpace IE.

S204: When using the short DRX cycle, the terminal monitors the powersaving signal in the search space based on the second group ofconfiguration parameters of the search space.

Optionally, step S204 may be expressed as follows: The terminalmonitors, in the search space based on the second group of configurationparameters of the search space, the power saving signal associated withthe short DRX cycle.

It should be noted that, when the terminal uses the short DRX cycle, thenetwork device may determine, based on an actual requirement, whether tosend the power saving signal in the search space. However, regardless ofwhether the network device sends the power saving signal, the terminalneeds to monitor the power saving signal in the search space based onthe second group of configuration parameters of the search space.

Based on the technical solution shown in FIG. 9, when using the long DRXcycle, the terminal uses the first group of configuration parameters ofthe search space, to meet a requirement of the terminal for a cycle ofmonitoring the power saving signal in the long DRX cycle. When using theshort DRX cycle, the terminal uses the second group of configurationparameters of the search space, to meet a requirement of the terminalfor a cycle of monitoring the power saving signal in the short DRXcycle. In other words, in a scenario in which the power saving signalcan be applied to the long DRX cycle and the short DRX cycle, for adifferent DRX cycle, the terminal may use a group of configurationparameters corresponding to the DRX cycle, to ensure that the terminalcan normally monitor the power saving signal in the search space.

The embodiment shown in FIG. 9 is described below by using an examplewith reference to FIG. 10.

The terminal enters a mode of the long DRX cycle before a long DRX cycle#1. Therefore, the network device determines, based on the first groupof configuration parameters of the search space (for example, themonitoring cycle in the first group of configuration parameters is afirst value), that monitoring occasions of the search space are amonitoring occasion #1 and a monitoring occasion #2, so that the networkdevice sends a power saving signal in the search space on the monitoringoccasion #1 and the monitoring occasion #2 of the search space.Correspondingly, the terminal monitors the power saving signal in thesearch space on the monitoring occasion #1 and the monitoring occasion#2 of the search space. The terminal enters a mode of the short DRXcycle before a short DRX cycle #1. Therefore, the network devicedetermines, based on the second group of configuration parameters of thesearch space (for example, the monitoring cycle in the second group ofconfiguration parameters is a first value), that monitoring occasions ofthe search space are a monitoring occasion #3, a monitoring occasion #4,a monitoring occasion #5, and a monitoring occasion #6, so that thenetwork device sends a power saving signal in the search space on themonitoring occasion #3, the monitoring occasion #4, the monitoringoccasion #5, and the monitoring occasion #6 of the search space.Correspondingly, the terminal monitors the power saving signal in thesearch space on the monitoring occasion #3, the monitoring occasion #4,the monitoring occasion #5, and the monitoring occasion #6 of the searchspace.

In other words, a long DRX cycle #2 is used as an example. The networkdevice determines, based on the first group of configuration parametersof the search space (for example, the monitoring cycle in the firstgroup of configuration parameters is a first value), that a monitoringoccasion of the search space is a monitoring occasion #2, so that thenetwork device sends, in the search space on the monitoring occasion #2of the search space, a power saving signal associated with the long DRXcycle #2. Correspondingly, the terminal monitors, in the search space onthe monitoring occasion #2 of the search space, the power saving signalassociated with the long DRX cycle #2. A short DRX cycle #2 is used asan example. The network device determines, based on the second group ofconfiguration parameters of the search space (for example, themonitoring cycle in the first group of configuration parameters is afirst value), that a monitoring occasion of the search space is amonitoring occasion #4, so that the network device sends, in the searchspace on the monitoring occasion #4 of the search space, a power savingsignal associated with the short DRX cycle #2. Correspondingly, theterminal monitors, in the search space on the monitoring occasion #4 ofthe search space, the power saving signal associated with the short DRXcycle #2.

The following describes this solution with reference to embodiments ofsome actual application scenarios.

For example, with reference to FIG. 7, when a user uses a mobile phoneto watch an online video, a requirement on a service delay is relativelylow. In this case, the mobile phone may use a long DRX cycle, and alength of the long DRX cycle may be 640 ms, that is, the mobile phonemonitors, every 640 ms (that is, on duration of the short DRX cycle),scheduling information sent by a base station. If the mobile phone hasfinished buffering the video data and does not need to receive the videodata temporarily, the mobile phone does not need to receive, within aperiod of time (for example, several long DRX cycles), schedulinginformation sent by the base station. In this case, the base station maysend a power saving signal to the mobile phone, to indicate that themobile phone may not monitor scheduling information in one or more longDRX cycles. Specifically, the base station may determine a monitoringoccasion of the search space based on the first group of configurationparameters of the search space, and send a power saving signal on themonitoring occasion of the search space. Correspondingly, the mobilephone may determine the monitoring occasion of the search space based onthe first group of configuration parameters of the search space, andmonitor the power saving signal on the monitoring occasion of the searchspace.

For example, with reference to FIG. 8, when a user uses a mobile phoneto play an online game, a requirement of the online game on a servicedelay is relatively high. In this case, the mobile phone may use a shortDRX cycle, and a length of the short DRX cycle may be 40 ms, that is,the mobile phone monitors, every 40 ms (that is, on duration of theshort DRX cycle), scheduling information sent by a base station. In agame loading process, the mobile phone does not need to perform datainteraction with the base station temporarily. In this case, the basestation may send a power saving signal to the mobile phone, to indicatethat the mobile phone may not monitor scheduling information in one ormore short DRX cycles. Specifically, the base station may determine amonitoring occasion of the search space based on the second group ofconfiguration parameters of the search space, and send a power savingsignal on the monitoring occasion of the search space. Correspondingly,the mobile phone may determine the monitoring occasion of the searchspace based on the second group of configuration parameters of thesearch space, and monitor the power saving signal on the monitoringoccasion of the search space.

FIG. 11 shows another search space monitoring method according to anembodiment of this application. The method includes the following steps.

S301: A network device determines M candidate monitoring occasions of asearch space.

For related descriptions of a power saving signal, refer to thedescriptions in the embodiment shown in FIG. 5. Details are notdescribed herein again.

The search space is a search space used to carry the power savingsignal. For a method for configuring, by the network device, the searchspace used to carry the power saving signal for the terminal, refer torelated descriptions in the embodiment shown in FIG. 5. Details are notdescribed herein again.

It should be noted that the monitoring occasion includes a period ofconsecutive time units in time domain, and the time unit may be an OFDMsymbol. The network device may send signaling such as a PDCCH on themonitoring occasion of the search space. Correspondingly, the terminalmay monitor the search space on the monitoring occasion, to receive thesignaling sent by the network device.

S302: The network device determines N target monitoring occasions fromthe M candidate monitoring occasions based on a time domain location ofon duration of a DRX cycle used by the terminal.

The DRX cycle may be a DRX cycle associated with the power savingsignal. Alternatively, the DRX cycle is a DRX cycle that is being usedby the terminal or a DRX cycle that is to be used by the terminal. N isa positive integer less than or equal to M.

Design 1: The target monitoring occasion is before the on duration ofthe DRX cycle used by the terminal, and is closest to the on duration ofthe DRX cycle used by the terminal.

Based on the design 1, the M candidate monitoring occasions may bedetermined based on configuration information of the search space, and Mis a positive integer. For a method for determining the M candidatemonitoring occasions, refer to the conventional technology. Details arenot described herein.

For example, with reference to FIG. 12, for a search space, a candidatemonitoring occasion #1 to a candidate monitoring occasion #8 exist intime domain. For a long DRX cycle #1, the candidate monitoring occasion#1 is before on duration of the long DRX cycle #1 and is closest to theon duration of the long DRX cycle #1. Therefore, the candidatemonitoring occasion #1 is the target monitoring occasion. For a long DRXcycle #2, the candidate monitoring occasion #3 is before on duration ofthe long DRX cycle #2 and is closest to the on duration of the long DRXcycle #2. Therefore, the candidate monitoring occasion #3 is the targetmonitoring occasion. For a short DRX cycle #1, the candidate monitoringoccasion #5 is before on duration of the short DRX cycle #1 and isclosest to the on duration of the short DRX cycle #1. Therefore, thecandidate monitoring occasion #5 is the target monitoring occasion. Byanalogy, it may be determined that the candidate monitoring occasion #6,the candidate monitoring occasion #7, and the candidate monitoringoccasion #8 are all target monitoring occasions.

Design 2: The N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle.

Based on the design 2, for each of the M candidate monitoring occasions,a difference between a start time of the candidate monitoring occasionand a start time of the DRX cycle is greater than or equal to a firstpreset value; or a difference between an end time of the candidatemonitoring occasion and a start time of the DRX cycle is greater than orequal to a first preset value.

In this embodiment of this application, the first preset value isdefined in a standard, or is preconfigured by the network device for theterminal, or is determined through negotiation between the terminal andthe network device.

The difference between the start time of the candidate monitoringoccasion and the start time of the DRX cycle may be referred to as afirst offset value. This is not limited in this embodiment of thisapplication.

Based on the design 2, a value of N is preset (that is, defined in astandard), or is preconfigured by the network device for the terminal,or is determined through negotiation between the terminal and thenetwork device.

For example, with reference to FIG. 13, it is assumed that N is equal to3. For a search space, a candidate monitoring occasion #1 to a candidatemonitoring occasion #10 exist in opportunity for DRX of a long DRX cycle#1. Therefore, target monitoring occasions associated with on durationof a short DRX cycle #1 are the candidate monitoring occasion #8, thecandidate monitoring occasion #9, and the candidate monitoring occasion#10. A candidate monitoring occasion #11 to a candidate monitoringoccasion #14 exist in opportunity for DRX of the short DRX cycle #1.Therefore, target monitoring occasions associated with on duration of ashort DRX cycle #2 are the candidate monitoring occasion #12, thecandidate monitoring occasion #13, and the candidate monitoring occasion#14. A candidate monitoring occasion #15 to a candidate monitoringoccasion #18 exist in opportunity for DRX of the short DRX cycle #2.Therefore, target monitoring occasions associated with on duration of anext DRX cycle are the candidate monitoring occasion #16, the candidatemonitoring occasion #17, and the candidate monitoring occasion #18.

Design 3: The N monitoring occasions are N candidate monitoringoccasions in a time window.

Based on the design 3, the M candidate monitoring occasions may bedetermined based on configuration information of the search space, and Mis a positive integer. For a method for determining the M candidatemonitoring occasions, refer to the conventional technology. Details arenot described herein.

It may be understood that the time window is essentially a time period.For a current DRX cycle, a difference between a start time of a timewindow corresponding to the current DRX cycle and a start time of onduration of a next DRX cycle is equal to a second preset value, and adifference between an end time of the time window corresponding to thecurrent DRX cycle and the start time of the on duration of the next DRXcycle is equal to a third preset value.

The difference between the start time of the time window and the starttime of the on duration of the DRX cycle may be referred to as a secondoffset value. The difference between the end time of the time window andthe start time of the on duration of the DRX cycle may be referred to asa third offset value. This is not limited in this embodiment of thisapplication.

The second preset value is defined in a standard, or is preconfigured bythe network device for the terminal, or is determined throughnegotiation between the terminal and the network device. The thirdpreset value is defined in a standard, or is preconfigured by thenetwork device for the terminal, or is determined through negotiationbetween the terminal and the network device.

That is, the network device may determine, based on the second offsetvalue and the third offset value, the time window corresponding to theDRX cycle, and further determine the N target monitoring occasions fromthe M candidate monitoring occasions based on the time window in the DRXcycle.

In this way, N target monitoring occasions in a short DRX cycle are Ncandidate monitoring occasions in a time window corresponding to theshort DRX cycle. N target monitoring occasions in a long DRX cycle are Ncandidate monitoring occasions in a time window corresponding to thelong DRX cycle.

Based on the design 3, a value of N is not fixed. It may be understoodthat the value of N is directly proportional to a size of the timewindow (or a length of the time window).

Optionally, a second offset value corresponding to the long DRX cyclemay be the same as a second offset value corresponding to the short DRXcycle, and a third offset value corresponding to the long DRX cycle maybe the same as a third offset value corresponding to the short DRXcycle. Therefore, a length of the time window corresponding to the longDRX cycle may be the same as a length of the time window correspondingto the short DRX cycle.

For example, with reference to FIG. 14, for a search space, a candidatemonitoring occasion #0 to a candidate monitoring occasion #11 exist inopportunity for DRX of a long DRX cycle #1. The candidate monitoringoccasion #9 and the candidate monitoring occasion #10 are in a timewindow, and therefore target monitoring occasions of the long DRX cycle#1 are the candidate monitoring occasion #9 and the candidate monitoringoccasion #10. A candidate monitoring occasion #12 to a candidatemonitoring occasion #17 exist in a short DRX cycle #1. The candidatemonitoring occasion #15 and the candidate monitoring occasion #16 are ina time window, and therefore target monitoring occasions of the shortDRX cycle #1 are the candidate monitoring occasion #15 and the candidatemonitoring occasion #16. A candidate monitoring occasion #18 to acandidate monitoring occasion #23 exist in a short DRX cycle #2. Thecandidate monitoring occasion #21 and the candidate monitoring occasion#22 are in a time window, and therefore target monitoring occasions ofthe short DRX cycle #2 are the candidate monitoring occasion #21 and thecandidate monitoring occasion #22.

Optionally, a second offset value corresponding to the long DRX cyclemay be different from a second offset value corresponding to the shortDRX cycle, and/or a third offset value corresponding to the long DRXcycle may be different from a third offset value corresponding to theshort DRX cycle. Therefore, a length of the time window corresponding tothe long DRX cycle may be different from a length of the time windowcorresponding to the short DRX cycle.

For example, a length of the time window corresponding to the long DRXcycle is greater than a length of the time window corresponding to theshort DRX cycle.

For example, with reference to FIG. 15, for a search space, a candidatemonitoring occasion #0 to a candidate monitoring occasion #11 exist inopportunity for DRX of a long DRX cycle #1. The candidate monitoringoccasion #7 to the candidate monitoring occasion #10 are in a timewindow, and therefore target monitoring occasions of the long DRX cycle#1 are the candidate monitoring occasion #7 to the candidate monitoringoccasion #10. A candidate monitoring occasion #12 to a candidatemonitoring occasion #17 exist in a short DRX cycle #1. The candidatemonitoring occasion #15 and the candidate monitoring occasion #16 are ina time window, and therefore target monitoring occasions of the shortDRX cycle #1 are the candidate monitoring occasion #15 and the candidatemonitoring occasion #16. A candidate monitoring occasion #18 to acandidate monitoring occasion #23 exist in a short DRX cycle #2. Thecandidate monitoring occasion #21 and the candidate monitoring occasion#22 are in a time window, and therefore target monitoring occasions ofthe short DRX cycle #2 are the candidate monitoring occasion #21 and thecandidate monitoring occasion #22.

Optionally, based on the foregoing design 1, design 2, or design 3, themonitoring cycle of the search space is less than or equal to the shortDRX cycle, to ensure that when the terminal uses the short DRX cycle,one or more corresponding target monitoring occasions exist in eachshort DRX cycle, thereby preventing the terminal from missing detectinga power saving signal.

If the monitoring cycle of the search space is less than or equal to theshort DRX cycle (that is, the monitoring cycle of the search space isthe same as the short DRX cycle in terms of a time length), and a propermonitoring offset value is used for the search space, when the terminaluses the short DRX cycle, all monitoring occasions of the search spaceare target monitoring occasions. This helps reduce complexity ofdetermining the target monitoring occasion by the terminal. In addition,because the long DRX cycle is generally L times the short DRX cycle,when the terminal uses the long DRX cycle, the terminal may alsodetermine one or more target monitoring occasions from the L consecutivemonitoring occasions. This also helps reduce complexity of determiningthe target monitoring occasion by the terminal. L is a positive integer.

Certainly, a monitoring cycle of the search space may alternatively bedifferent from a short DRX cycle in terms of a time length. This is notlimited in this embodiment of this application.

S303: The network device sends the power saving signal on the N targetmonitoring occasions in the search space.

It may be understood that the network device does not send the powersaving signal on a non-target monitoring occasion of the search space.

S304: The terminal determines M candidate monitoring occasions of asearch space.

S305: The terminal determines N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a DRX cycle.

For specific implementation of steps S304 and S305, refer to thedescriptions in steps S301 and S302. Details are not described hereinagain.

S306: The terminal monitors the power saving signal on the N targetmonitoring occasions in the search space.

It may be understood that the terminal does not monitor the power savingsignal on a non-target monitoring occasion of the search space, so as toreduce power consumption of the terminal.

It should be noted that the network device may determine, based on anactual requirement, whether to send the power saving signal in thesearch space. However, regardless of whether the network device sendsthe power saving signal, the terminal needs to monitor the power savingsignal on the target monitoring occasion of the search space, so as toavoid missing detecting a power saving signal.

Based on the technical solution shown in FIG. 11, the terminaldetermines the target monitoring occasion based on the time domainlocation of the on duration of the DRX cycle. To be specific, when theterminal uses a long DRX cycle, the terminal may determine the targetmonitoring occasion based on a time domain location of on duration ofthe long DRX cycle. When the terminal uses a short DRX cycle, theterminal may determine the target monitoring occasion based on a timedomain location of on duration of the short DRX cycle. The targetmonitoring occasion determined by the terminal is adapted to a DRX cycleused by the terminal. In this way, regardless of the long DRX cycle orthe short DRX cycle, the terminal can normally monitor the power savingsignal in the search space on a proper monitoring occasion (that is, thetarget monitoring occasion).

The following describes this solution with reference to embodiments ofsome actual application scenarios.

For example, with reference to FIG. 7, when a user uses a mobile phoneto watch an online video, a requirement on a service delay is relativelylow. In this case, the mobile phone may use a long DRX cycle, and alength of the long DRX cycle may be 640 ms, that is, the mobile phonemonitors, every 640 ms (that is, on duration of the short DRX cycle),scheduling information sent by a base station. If the mobile phone hasfinished buffering the video data and does not need to receive the videodata temporarily, the mobile phone does not need to receive, within aperiod of time (for example, several long DRX cycles), schedulinginformation sent by the base station. In this case, the base station maysend a power saving signal to the mobile phone, to indicate that themobile phone may not monitor scheduling information in one or more longDRX cycles. Specifically, the base station may determine M candidatemonitoring occasions based on a configuration parameter of the searchspace, and then determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of the long DRX cycle. Therefore, the base station sends thepower saving signal on the N target monitoring occasions in the searchspace. Correspondingly, the mobile phone may determine M candidatemonitoring occasions based on a configuration parameter of the searchspace, and then determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of the long DRX cycle. Therefore, the mobile phone sends thepower saving signal on the N target monitoring occasions in the searchspace.

For example, with reference to FIG. 8, when a user uses a mobile phoneto play an online game, a requirement on a service delay is relativelyhigh. In this case, the mobile phone may use a short DRX cycle, and alength of the short DRX cycle may be 40 ms, that is, the mobile phonemonitors, every 40 ms (that is, on duration of the short DRX cycle),scheduling information sent by a base station. In a game loadingprocess, the mobile phone does not need to perform data interaction withthe base station temporarily. In this case, the base station may send apower saving signal to the mobile phone, to indicate that the mobilephone may not monitor scheduling information in one or more short DRXcycles. Specifically, the base station may determine M candidatemonitoring occasions based on a configuration parameter of the searchspace, and then determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of the short DRX cycle. Therefore, the base station sends thepower saving signal on the N target monitoring occasions in the searchspace. Correspondingly, the mobile phone may determine M candidatemonitoring occasions based on a configuration parameter of the searchspace, and then determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of the short DRX cycle. Therefore, the mobile phone sends thepower saving signal on the N target monitoring occasions in the searchspace.

The foregoing mainly describes the solutions provided in the embodimentsof this application from a perspective of interaction between networkelements. It may be understood that, to implement the foregoingfunctions, each of network elements such as the terminal and the networkdevice includes a corresponding hardware structure and/or softwaremodule for performing each function. A person skilled in the art shouldeasily be aware that, in combination with units and algorithm steps ofthe examples described in the embodiments disclosed in thisspecification, this application may be implemented by hardware or acombination of hardware and computer software. Whether a function isperformed by hardware or hardware driven by computer software depends onparticular applications and design constraints of the technicalsolutions. A person skilled in the art may use different methods toimplement the described functions for each particular application, butit should not be considered that the implementation goes beyond thescope of this application.

In the embodiments of this application, function modules of the terminaland the network device may be obtained through division based on theforegoing method examples. For example, each function module may beobtained through division based on each corresponding function, or twoor more functions may be integrated into one processing module. Theintegrated module may be implemented in a form of hardware, or may beimplemented in a form of a software function module. It should be notedthat module division in the embodiments of this application is anexample, and is merely a logical function division. During actualimplementation, another division manner may be used. The followingprovides descriptions by using an example in which each function moduleis obtained through division based on a corresponding function.

FIG. 16 is a schematic diagram of a structure of a communicationsapparatus according to an embodiment of this application. As shown inFIG. 16, the communications apparatus includes a processing module 201and a communications module 202. The processing module 201 may include afirst processing module and a second processing module.

Optionally, the communications apparatus may perform at least one of thefollowing solutions:

Solution 1: The first processing module is configured to: when aterminal uses a long DRX cycle, monitor a power saving signal in a firstsearch space, and skip monitoring the power saving signal in a secondsearch space, where the power saving signal is used to indicate powersaving information of the terminal. The second processing module isconfigured to: when the terminal uses a short DRX cycle, monitor thepower saving signal in the second search space, and skip monitoring thepower saving signal in the first search space.

For related descriptions of the power saving information, the firstsearch space, and the second search space, refer to the embodiment shownin FIG. 5. Details are not described herein again.

Solution 2: The first processing module is configured to: when aterminal uses a long DRX cycle, monitor a power saving signal in asearch space based on a first group of configuration parameters of thesearch space, where the power saving signal is used to indicate powersaving information of the terminal. The second processing module isconfigured to: when the terminal uses a short DRX cycle, monitor thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

For related descriptions of the power saving information, the searchspace, the first group of configuration parameters, and the second groupof configuration parameters, refer to the embodiment shown in FIG. 9.Details are not described herein again.

In a possible design, the communications module 202 is configured toreceive configuration information of the search space, where theconfiguration information of the search space is used to indicate thefirst group of configuration parameters and the second group ofconfiguration parameters.

In a possible design, the communications module 202 is configured to:receive configuration information of the search space, and receiveindication information. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

Solution 3: The first processing module is configured to: determine Mcandidate monitoring occasions of a search space, where M is a positiveinteger; and determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a DRX cycle, where N is a positive integer less than orequal to M. The second processing module is configured to monitor apower saving signal on the N target monitoring occasions in the searchspace, where the power saving signal is used to indicate power savinginformation of a terminal.

For related information about the power saving signal, the search space,and the target monitoring occasion, refer to the embodiment shown inFIG. 11. Details are not described herein again.

In an example, with reference to the communications apparatus shown inFIG. 4, the communications module 202 in FIG. 16 may be implemented bythe communications interface 104 in FIG. 4, and the processing module201 in FIG. 16 may be implemented by the processor 101 in FIG. 4. Thisis not limited in this embodiment of this application.

FIG. 17 is a schematic diagram of a structure of a communicationsapparatus according to an embodiment of this application. As shown inFIG. 17, the communications apparatus includes a processing module 301and a communications module 302. The communications module 302 mayinclude a first communications module and a second communicationsmodule.

Optionally, the communications apparatus may perform at least one of thefollowing solutions:

Solution 1: The first communications module is configured to: when aterminal uses a long DRX cycle, send a power saving signal in a firstsearch space, and skip sending the power saving signal in a secondsearch space, where the power saving signal is used to indicate powersaving information of the terminal. The second communications module isconfigured to: when the terminal uses a short DRX cycle, send the powersaving signal in the second search space, and skip sending the powersaving signal in the first search space.

For related descriptions of the power saving information, the firstsearch space, and the second search space, refer to the embodiment shownin FIG. 5. Details are not described herein again.

Solution 2: The first communications module is configured to: when aterminal uses a long DRX cycle, send a power saving signal in a searchspace based on a first group of configuration parameters of the searchspace, where the power saving signal is used to indicate power savinginformation of the terminal. The second communications module isconfigured to: when the terminal uses a short DRX cycle, send the powersaving signal in the search space based on a second group ofconfiguration parameters of the search space.

For related descriptions of the power saving information, the searchspace, the first group of configuration parameters, and the second groupof configuration parameters, refer to the embodiment shown in FIG. 9.Details are not described herein again.

In a possible design, the first communications module/the secondcommunications module is further configured to send configurationinformation of the search space to the terminal, where the configurationinformation of the search space is used to indicate the first group ofconfiguration parameters and the second group of configurationparameters.

In a possible design, the first communications module/the secondcommunications module is further configured to: send configurationinformation of the search space to the terminal, and send indicationinformation to the terminal. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

Solution 3: The processing module 301 is configured to: determine Mcandidate monitoring occasions of a search space, where M is a positiveinteger; and determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a DRX cycle used by a terminal, where N is a positiveinteger less than or equal to M. The communications module 302 isconfigured to send a power saving signal on the N target monitoringoccasions in the search space, where the power saving signal is used toindicate power saving information of the terminal.

For related information about the power saving signal, the search space,and the target monitoring occasion, refer to the embodiment shown inFIG. 11. Details are not described herein again.

In an example, with reference to the communications apparatus shown inFIG. 4, the communications module 302 in FIG. 17 may be implemented bythe communications interface 104 in FIG. 4, and the processing module301 in FIG. 17 may be implemented by the processor 101 in FIG. 4. Thisis not limited in this embodiment of this application.

An embodiment of this application further provides a computer-readablestorage medium. The computer-readable storage medium stores computerinstructions. When the computer-readable storage medium runs on acommunications apparatus, the communications apparatus is enabled toperform the method shown in FIG. 5, FIG. 9, or FIG. 11. The computerinstructions may be stored in a computer-readable storage medium or maybe transmitted from a computer-readable storage medium to anothercomputer-readable storage medium. For example, the computer instructionsmay be transmitted from a website, computer, server, or data center toanother website, computer, server, or data center in a wired (forexample, a coaxial cable, an optical fiber, or a digital subscriber line(digital subscriber line. DSL)) or wireless (for example, infrared,radio, or microwave) manner. The computer-readable storage medium may beany usable medium accessible by a computer, or a data storage device,such as a server or a data center, integrating one or more usable media.The usable medium may be a magnetic medium (for example, a floppy disk,a hard disk, or a magnetic tape), an optical medium, a semiconductormedium (for example, a solid-state drive (solid-state drive, SSD)), orthe like.

An embodiment of this application further provides a computer programproduct including computer instructions. When the computer programproduct is run on a communications apparatus, the communicationsapparatus is enabled to perform the method shown in FIG. 5, FIG. 9, orFIG. 11.

An embodiment of this application further provides a communicationssystem. The communications system includes a network device and aterminal. The terminal is configured to perform the technical solutionshown in FIG. 5, FIG. 9, or FIG. 11, and the network device isconfigured to perform the technical solution shown in FIG. 5, FIG. 9, orFIG. 11.

FIG. 18 is a schematic diagram of a structure of a chip according to anembodiment of this application. The chip shown in FIG. 18 may be ageneral-purpose processor, or may be a dedicated processor. The chipincludes a processor 401. The processor 401 is configured to support acommunications apparatus in performing the technical solution shown inFIG. 5, FIG. 9, or FIG. 11.

Optionally, the chip further includes a transceiver 402. The transceiver402 is configured to support, under control of the processor 401, acommunications apparatus in performing the technical solution shown inFIG. 5. FIG. 9, or FIG. 11.

Optionally, the chip shown in FIG. 18 may further include a storagemedium 403.

It should be noted that the chip shown in FIG. 18 may be implemented bythe following circuit or component: one or more field programmable gatearrays (field programmable gate array, FPGA), a programmable logicdevice (programmable logic device, PLD), a controller, a state machine,gate logic, a discrete hardware component, any other appropriatecircuit, or any combination of circuits that can perform variousfunctions described in this application.

The terminal, the network device, the computer storage medium, thecomputer program product, and the chip provided in the embodiments ofthis application are all configured to perform the methods providedabove. Therefore, for beneficial effects that can be achieved by theterminal, the network device, the computer storage medium, the computerprogram product, and the chip, refer to the beneficial effectscorresponding to the methods provided above. Details are not describedherein again.

With reference to the foregoing descriptions, this application furtherprovides the following embodiments:

Embodiment 1: A search space monitoring method is provided. The methodincludes:

When using a long DRX cycle, a terminal monitors a power saving signalin a first search space, and does not monitor the power saving signal ina second search space, where the power saving signal is used to indicatepower saving information of the terminal.

When using a short DRX cycle, the terminal monitors the power savingsignal in the second search space, and does not monitor the power savingsignal in the first search space.

Embodiment 2: According to the search space monitoring method inEmbodiment 1, the power saving information includes at least one of thefollowing: whether the terminal monitors a PDCCH in a DRX cycleassociated with the power saving signal; a minimum scheduling timeinterval indication; a CSI measurement trigger indication; a BWPswitching indication; a search space and/or a CORESET that the terminalneeds to monitor in the DRX cycle associated with the power savingsignal; a monitoring cycle in which the terminal monitors the PDCCH inthe DRX cycle associated with the power saving signal; and skippingduration used by the terminal in the DRX cycle associated with the powersaving signal.

Embodiment 3: According to the search space monitoring method inEmbodiment 1 or Embodiment 2, a monitoring cycle of the first searchspace is the same as the long DRX cycle in terms of a time length, and amonitoring cycle of the second search space is the same as the short DRXcycle in terms of a time length.

Embodiment 4: According to the search space monitoring method accordingto any one of Embodiment 1 to Embodiment 3, a monitoring offset value ofthe first search space is different from a monitoring offset value ofthe second search space.

Embodiment 5: A communications method is provided. The method includes:

When a terminal uses a long DRX cycle, a network device sends a powersaving signal in a first search space, and does not send the powersaving signal in a second search space, where the power saving signal isused to indicate power saving information of the terminal.

When the terminal uses a short DRX cycle, the network device sends thepower saving signal in the second search space, and does not send thepower saving signal in the first search space.

Embodiment 6: According to the communications method in Embodiment 5,the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 7: According to the communications method in Embodiment 5 orEmbodiment 6, a monitoring cycle of the first search space is the sameas the long DRX cycle in terms of a time length, and a monitoring cycleof the second search space is the same as the short DRX cycle in termsof a time length.

Embodiment 8: According to the communications method according to anyone of Embodiment 5 to Embodiment 7, a monitoring offset value of thefirst search space is different from a monitoring offset value of thesecond search space.

Embodiment 9: A communications apparatus is provided. The communicationsapparatus may be a terminal, a chip in the terminal, or a system onchip. The communications apparatus includes a processor and a memory.The memory stores instructions. When the instructions are executed bythe processor, the communications apparatus is enabled to perform thefollowing steps: when using a long DRX cycle, monitoring a power savingsignal in a first search space, and skipping monitoring the power savingsignal in a second search space, where the power saving signal is usedto indicate power saving information of the terminal; and when using ashort DRX cycle, monitoring the power saving signal in the second searchspace, and skipping monitoring the power saving signal in the firstsearch space.

Embodiment 10: According to the communications apparatus in Embodiment9, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication, aCSI measurement trigger indication: a BWP switching indication, a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 11: According to the communications apparatus in Embodiment 9or Embodiment 10, a monitoring cycle of the first search space is thesame as the long DRX cycle in terms of a time length, and a monitoringcycle of the second search space is the same as the short DRX cycle interms of a time length.

Embodiment 12: According to the communications apparatus according toany one of Embodiment 9 to Embodiment 11, a monitoring offset value ofthe first search space is different from a monitoring offset value ofthe second search space.

Embodiment 13: A communications apparatus is provided. Thecommunications apparatus may be a network device, a chip in the networkdevice, or a system on chip. The communications apparatus includes aprocessor and a memory. The memory stores instructions. When theinstructions are executed by the processor, the communications apparatusis enabled to perform the following steps: when a terminal uses a longDRX cycle, sending a power saving signal in a first search space, andskipping sending the power saving signal in a second search space, wherethe power saving signal is used to indicate power saving information ofthe terminal, and when the terminal uses a short DRX cycle, sending thepower saving signal in the second search space, and skipping sending thepower saving signal in the first search space.

Embodiment 14: According to the communications apparatus in Embodiment13, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 15: According to the communications apparatus in Embodiment13 or Embodiment 14, a monitoring cycle of the first search space is thesame as the long DRX cycle in terms of a time length, and a monitoringcycle of the second search space is the same as the short DRX cycle interms of a time length.

Embodiment 16: According to the communications apparatus according toany one of Embodiment 13 to Embodiment 15, a monitoring offset value ofthe first search space is different from a monitoring offset value ofthe second search space.

Embodiment 17: A communications apparatus is provided, including a firstprocessing unit and a second processing unit. The first processingmodule is configured to: when a terminal uses a long DRX cycle, monitora power saving signal in a first search space, and skip monitoring thepower saving signal in a second search space, where the power savingsignal is used to indicate power saving information of the terminal. Thesecond processing module is configured to: when the terminal uses ashort DRX cycle, monitor the power saving signal in the second searchspace, and skip monitoring the power saving signal in the first searchspace.

Embodiment 18: According to the communications apparatus in Embodiment17, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 19: According to the communications apparatus in Embodiment17 or Embodiment 18, a monitoring cycle of the first search space is thesame as the long DRX cycle in terms of a time length, and a monitoringcycle of the second search space is the same as the short DRX cycle interms of a time length.

Embodiment 20: According to the communications apparatus according toany one of Embodiment 17 to Embodiment 19, a monitoring offset value ofthe first search space is different from a monitoring offset value ofthe second search space.

Embodiment 21: A communications apparatus is provided, including a firstcommunications module and a second communications module. The firstcommunications module is configured to: when a terminal uses a long DRXcycle, send a power saving signal in a first search space, and skipsending the power saving signal in a second search space, where thepower saving signal is used to indicate power saving information of theterminal. The second communications module is configured to: when theterminal uses a short DRX cycle, send the power saving signal in thesecond search space, and skip sending the power saving signal in thefirst search space.

Embodiment 22: According to the communications apparatus in Embodiment21, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication: a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 23: According to the communications apparatus in Embodiment21 or Embodiment 22, a monitoring cycle of the first search space is thesame as the long DRX cycle in terms of a time length, and a monitoringcycle of the second search space is the same as the short DRX cycle interms of a time length.

Embodiment 24: According to the communications apparatus according toany one of Embodiment 21 to Embodiment 23, a monitoring offset value ofthe first search space is different from a monitoring offset value ofthe second search space.

Embodiment 25: A communications system is provided, including a terminaland a network device.

The terminal is configured to: when using a long DRX cycle, monitor apower saving signal in a first search space, and skip monitoring thepower saving signal in a second search space, where the power savingsignal is used to indicate power saving information of the terminal; andwhen using a short DRX cycle, monitor the power saving signal in thesecond search space, and skip monitoring the power saving signal in thefirst search space.

The network device is configured to: when the terminal uses a long DRXcycle, send a power saving signal in a first search space, and skipsending the power saving signal in a second search space, where thepower saving signal is used to indicate power saving information of theterminal; and when the terminal uses a short DRX cycle, send the powersaving signal in the second search space, and skip sending the powersaving signal in the first search space.

Embodiment 26: According to the communications system in Embodiment 25,the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 27: According to the communications system in Embodiment 25or Embodiment 26, a monitoring cycle of the first search space is thesame as the long DRX cycle in terms of a time length, and a monitoringcycle of the second search space is the same as the short DRX cycle interms of a time length.

Embodiment 28: According to the communications system according to anyone of Embodiment 25 to Embodiment 27, a monitoring offset value of thefirst search space is different from a monitoring offset value of thesecond search space.

Embodiment 29: A computer program product is provided. When the computerprogram product is run on a computer, the computer is enabled to performthe method in any one of Embodiment 1 to Embodiment 8.

Embodiment 30: A computer-readable storage medium is provided. Thecomputer-readable storage medium stores instructions, and when theinstructions are run on a computer, the computer is enabled to performthe method in any one of Embodiment 1 to Embodiment 8.

Embodiment 31: A chip is provided. The chip includes a processor, andwhen the processor executes instructions, the processor is configured toperform the method in any one of Embodiment 1 to Embodiment 8. Theinstructions may be from a memory inside the chip, or may be from amemory outside the chip. Optionally, the chip further includes aninput/output circuit.

Embodiment 32: A search space monitoring method is provided. The methodincludes:

When using a long DRX cycle, a terminal monitors a power saving signalin a search space based on a first group of configuration parameters ofthe search space, where the power saving signal is used to indicatepower saving information of the terminal.

When using a short DRX cycle, the terminal monitors the power savingsignal in the search space based on a second group of configurationparameters of the search space.

Embodiment 33: According to the search space monitoring method inEmbodiment 32, the power saving information includes at least one of thefollowing: whether the terminal monitors a PDCCH in a DRX cycleassociated with the power saving signal; a minimum scheduling timeinterval indication; a CSI measurement trigger indication; a BWPswitching indication; a search space and/or a CORESET that the terminalneeds to monitor in the DRX cycle associated with the power savingsignal; a monitoring cycle in which the terminal monitors the PDCCH inthe DRX cycle associated with the power saving signal; and skippingduration used by the terminal in the DRX cycle associated with the powersaving signal.

Embodiment 34: According to the search space monitoring method inEmbodiment 32 or Embodiment 33, the method further includes: Theterminal receives configuration information of the search space, wherethe configuration information of the search space is used to indicatethe first group of configuration parameters and the second group ofconfiguration parameters.

Embodiment 35: According to the search space monitoring method inEmbodiment 32 or Embodiment 33, the method further includes: Theterminal receives configuration information of the search space, wherethe configuration information of the search space is used to indicate aparameter other than a monitoring cycle and a monitoring offset value inthe first group of configuration parameters, and a parameter other thana monitoring cycle and a monitoring offset value in the second group ofconfiguration parameters. The terminal receives indication information,where the indication information is used to indicate the monitoringcycle and the monitoring offset value in the first group ofconfiguration parameters, and the monitoring cycle and the monitoringoffset value in the second group of configuration parameters.

Embodiment 36: According to the search space monitoring method in anyone of Embodiment 32 to Embodiment 35, the monitoring cycle in the firstgroup of configuration parameters is the same as the long DRX cycle interms of a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 37: According to the search space monitoring method in anyone of Embodiment 32 to Embodiment 36, the monitoring offset value inthe first group of configuration parameters is different from themonitoring offset value in the second group of configuration parameters.

Embodiment 38: A communications method is provided. The method includes:

When a terminal uses a long discontinuous reception DRX cycle, a networkdevice sends a power saving signal in a search space based on a firstgroup of configuration parameters of the search space, where the powersaving signal is used to indicate power saving information of theterminal.

When the terminal uses a short DRX cycle, the network device sends thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

Embodiment 39: According to the communications method in Embodiment 38,the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 40: According to the communications method in Embodiment 39or Embodiment 40, the method further includes: The network device sendsconfiguration information of the search space to the terminal, where theconfiguration information of the search space is used to indicate thefirst group of configuration parameters and the second group ofconfiguration parameters.

Embodiment 41: According to the communications method in Embodiment 39or Embodiment 40, the method further includes: The network device sendsconfiguration information of the search space to the terminal, where theconfiguration information of the search space is used to indicate aparameter other than a monitoring cycle and a monitoring offset value inthe first group of configuration parameters, and a parameter other thana monitoring cycle and a monitoring offset value in the second group ofconfiguration parameters. The network device sends indicationinformation to the terminal, where the indication information is used toindicate the monitoring cycle and the monitoring offset value in thefirst group of configuration parameters, and the monitoring cycle andthe monitoring offset value in the second group of configurationparameters.

Embodiment 42: According to the communications method in any one ofEmbodiment 38 to Embodiment 41, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 43: According to the communications method in any one ofEmbodiment 38 to Embodiment 42, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 44: A communications apparatus is provided. Thecommunications apparatus may be a terminal, a chip in the terminal, or asystem on chip. The communications apparatus includes a processor and amemory. The memory stores instructions. When the instructions areexecuted by the processor, the communications apparatus is enabled toperform the following steps: when using a long DRX cycle, monitoring apower saving signal in a search space based on a first group ofconfiguration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal; andwhen using a short DRX cycle, monitoring the power saving signal in thesearch space based on a second group of configuration parameters of thesearch space.

Embodiment 45: According to the communications apparatus in Embodiment44, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 46: According to the communications apparatus in Embodiment44 or Embodiment 45, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following step: receiving configuration information of the searchspace, where the configuration information of the search space is usedto indicate the first group of configuration parameters and the secondgroup of configuration parameters.

Embodiment 47: According to the communications apparatus in Embodiment44 or Embodiment 45, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following steps: receiving configuration information of the searchspace, where the configuration information of the search space is usedto indicate a parameter other than a monitoring cycle and a monitoringoffset value in the first group of configuration parameters, and aparameter other than a monitoring cycle and a monitoring offset value inthe second group of configuration parameters; and receiving indicationinformation, where the indication information is used to indicate themonitoring cycle and the monitoring offset value in the first group ofconfiguration parameters, and the monitoring cycle and the monitoringoffset value in the second group of configuration parameters.

Embodiment 48: According to the communications apparatus in any one ofEmbodiment 44 to Embodiment 47, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 49: According to the communications apparatus in any one ofEmbodiment 44 to Embodiment 48, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 50: A communications apparatus is provided. Thecommunications apparatus may be a network device, a chip in the networkdevice, or a system on chip. The communications apparatus includes aprocessor and a memory. The memory stores instructions. When theinstructions are executed by the processor, the communications apparatusis enabled to perform the following steps: when a terminal uses a longDRX cycle, sending a power saving signal in a search space based on afirst group of configuration parameters of the search space, where thepower saving signal is used to indicate power saving information of theterminal; and when the terminal uses a short DRX cycle, sending thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

Embodiment 51: According to the communications apparatus in Embodiment50, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 52: According to the communications apparatus in Embodiment50 or Embodiment 51, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following step: sending configuration information of the searchspace to the terminal, where the configuration information of the searchspace is used to indicate the first group of configuration parametersand the second group of configuration parameters.

Embodiment 53: According to the communications apparatus in Embodiment50 or Embodiment 51, when the instructions are executed by theprocessor, the communications apparatus is further enabled to performthe following steps: sending configuration information of the searchspace to the terminal, where the configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters;and sending indication information to the terminal, where the indicationinformation is used to indicate the monitoring cycle and the monitoringoffset value in the first group of configuration parameters, and themonitoring cycle and the monitoring offset value in the second group ofconfiguration parameters.

Embodiment 54: According to the communications apparatus in any one ofEmbodiment 50 to Embodiment 53, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 55: According to the communications apparatus in any one ofEmbodiment 50 to Embodiment 54, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 56: A communications apparatus is provided. Thecommunications apparatus includes a first processing module and a secondprocessing module. The first processing module is configured to: when aterminal uses a long DRX cycle, monitor a power saving signal in asearch space based on a first group of configuration parameters of thesearch space, where the power saving signal is used to indicate powersaving information of the terminal. The second processing module isconfigured to: when the terminal uses a short DRX cycle, monitor thepower saving signal in the search space based on a second group ofconfiguration parameters of the search space.

Embodiment 57: According to the communications apparatus in Embodiment56, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 58: According to the communications apparatus in Embodiment56 or Embodiment 57, the communications apparatus further includes acommunications module. The communications module is configured toreceive configuration information of the search space, where theconfiguration information of the search space is used to indicate thefirst group of configuration parameters and the second group ofconfiguration parameters.

Embodiment 59: According to the communications apparatus in Embodiment56 or Embodiment 57, the communications apparatus further includes acommunications module. The communications module is configured to:receive configuration information of the search space, and receiveindication information. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

Embodiment 60: According to the communications apparatus in any one ofEmbodiment 56 to Embodiment 59, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 61: According to the communications apparatus in any one ofEmbodiment 56 to Embodiment 60, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 62: A communications apparatus is provided. Thecommunications apparatus includes a first communications module and asecond communications module. The first communications module isconfigured to: when a terminal uses a long DRX cycle, send a powersaving signal in a search space based on a first group of configurationparameters of the search space, where the power saving signal is used toindicate power saving information of the terminal. The secondcommunications module is configured to: when the terminal uses a shortDRX cycle, send the power saving signal in the search space based on asecond group of configuration parameters of the search space.

Embodiment 63: According to the communications apparatus in Embodiment62, the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 64: According to the communications apparatus in Embodiment62 or Embodiment 63, the first communications module/the secondcommunications module is further configured to send configurationinformation of the search space to the terminal, where the configurationinformation of the search space is used to indicate the first group ofconfiguration parameters and the second group of configurationparameters.

Embodiment 65: According to the communications apparatus in Embodiment62 or Embodiment 63, the first communications module/the secondcommunications module is further configured to: send configurationinformation of the search space to the terminal, and send indicationinformation to the terminal. The configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters.The indication information is used to indicate the monitoring cycle andthe monitoring offset value in the first group of configurationparameters, and the monitoring cycle and the monitoring offset value inthe second group of configuration parameters.

Embodiment 66: According to the communications apparatus in any one ofEmbodiment 62 to Embodiment 65, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 67: According to the communications apparatus in any one ofEmbodiment 62 to Embodiment 66, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 68: A communications system is provided, including a terminaland a network device.

The terminal is configured to: when using a long DRX cycle, monitor apower saving signal in a search space based on a first group ofconfiguration parameters of the search space, where the power savingsignal is used to indicate power saving information of the terminal; andwhen using a short DRX cycle, monitor the power saving signal in thesearch space based on a second group of configuration parameters of thesearch space.

The network device is configured to: when the terminal uses a longdiscontinuous reception DRX cycle, send a power saving signal in asearch space based on a first group of configuration parameters of thesearch space, where the power saving signal is used to indicate powersaving information of the terminal; and when the terminal uses a shortDRX cycle, send the power saving signal in the search space based on asecond group of configuration parameters of the search space.

Embodiment 69: According to the communications system in Embodiment 68,the power saving information includes at least one of the following:whether the terminal monitors a PDCCH in a DRX cycle associated with thepower saving signal; a minimum scheduling time interval indication; aCSI measurement trigger indication; a BWP switching indication; a searchspace and/or a CORESET that the terminal needs to monitor in the DRXcycle associated with the power saving signal; a monitoring cycle inwhich the terminal monitors the PDCCH in the DRX cycle associated withthe power saving signal; and skipping duration used by the terminal inthe DRX cycle associated with the power saving signal.

Embodiment 70: According to the communications system in Embodiment 68or Embodiment 69, the network device is further configured to sendconfiguration information of the search space to the terminal, where theconfiguration information of the search space is used to indicate thefirst group of configuration parameters and the second group ofconfiguration parameters. The terminal is further configured to receiveconfiguration information of the search space, where the configurationinformation of the search space is used to indicate the first group ofconfiguration parameters and the second group of configurationparameters.

Embodiment 71: According to the communications system in Embodiment 68or Embodiment 69, the network device is further configured to: sendconfiguration information of the search space to the terminal, where theconfiguration information of the search space is used to indicate aparameter other than a monitoring cycle and a monitoring offset value inthe first group of configuration parameters, and a parameter other thana monitoring cycle and a monitoring offset value in the second group ofconfiguration parameters; and send indication information to theterminal, where the indication information is used to indicate themonitoring cycle and the monitoring offset value in the first group ofconfiguration parameters, and the monitoring cycle and the monitoringoffset value in the second group of configuration parameters. Theterminal is further configured to: receive configuration information ofthe search space, where the configuration information of the searchspace is used to indicate a parameter other than a monitoring cycle anda monitoring offset value in the first group of configurationparameters, and a parameter other than a monitoring cycle and amonitoring offset value in the second group of configuration parameters;and receive indication information, where the indication information isused to indicate the monitoring cycle and the monitoring offset value inthe first group of configuration parameters, and the monitoring cycleand the monitoring offset value in the second group of configurationparameters.

Embodiment 72: According to the communications system in any one ofEmbodiment 68 to Embodiment 71, the monitoring cycle in the first groupof configuration parameters is the same as the long DRX cycle in termsof a time length, and the monitoring cycle in the second group ofconfiguration parameters is the same as the short DRX cycle in terms ofa time length.

Embodiment 73: According to the communications system in any one ofEmbodiment 68 to Embodiment 72, the monitoring offset value in the firstgroup of configuration parameters is different from the monitoringoffset value in the second group of configuration parameters.

Embodiment 74: A computer program product is provided. When the computerprogram product is run on a computer, the computer is enabled to performthe method in any one of Embodiment 32 to Embodiment 43.

Embodiment 75: A computer-readable storage medium is provided. Thecomputer-readable storage medium stores instructions, and when theinstructions are run on a computer, the computer is enabled to performthe method in any one of Embodiment 32 to Embodiment 43.

Embodiment 76: A chip is provided. The chip includes a processor, andwhen the processor executes instructions, the processor is configured toperform the method in any one of Embodiment 32 to Embodiment 43. Theinstructions may be from a memory inside the chip, or may be from amemory outside the chip. Optionally, the chip further includes aninput/output circuit.

Embodiment 77: A search space monitoring method is provided. The methodincludes:

A terminal determines M candidate monitoring occasions of a searchspace, where M is a positive integer.

The terminal determines N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a discontinuous reception DRX cycle, where N is a positiveinteger less than or equal to M.

The terminal monitors a power saving signal on the N target monitoringoccasions in the search space, where the power saving signal is used toindicate power saving information of the terminal.

Embodiment 78: According to the search space monitoring method inEmbodiment 77, a monitoring cycle of the search space is the same as ashort DRX cycle in terms of a time length.

Embodiment 79: According to the search space monitoring method inEmbodiment 77 or Embodiment 78, the target monitoring occasion is beforethe on duration of the DRX cycle, and is closest to the on duration ofthe DRX cycle.

Embodiment 80: According to the search space monitoring method inEmbodiment 77, the N target monitoring occasions are N candidatemonitoring occasions that are in the M candidate monitoring occasionsand that are closest to the on duration of the DRX cycle; and for eachof the M candidate monitoring occasions, a difference between a starttime of the candidate monitoring occasion and a start time of the DRXcycle is greater than or equal to a first preset value.

Embodiment 81: According to the search space monitoring method inEmbodiment 80, a value of N is preset, or is configured by a networkdevice for the terminal.

Embodiment 82: According to the search space monitoring method inEmbodiment 77, the N target monitoring occasions are N candidatemonitoring occasions in a time window, a difference between a start timeof the time window and a start time of the on duration of the DRX cycleis equal to a second preset value, and a difference between an end timeof the time window and the start time of the on duration of the DRXcycle is equal to a third preset value.

Embodiment 83: According to the search space monitoring method in anyone of Embodiment 77 to Embodiment 82, the power saving informationincludes at least one of the following: whether the terminal monitors aPDCCH in a DRX cycle associated with the power saving signal; a minimumscheduling time interval indication; a CSI measurement triggerindication; a BWP switching indication; a search space and/or a CORESETthat the terminal needs to monitor in the DRX cycle associated with thepower saving signal; a monitoring cycle in which the terminal monitorsthe PDCCH in the DRX cycle associated with the power saving signal; andskipping duration used by the terminal in the DRX cycle associated withthe power saving signal.

Embodiment 84: A communications method is provided. The method includes:

A network device determines M candidate monitoring occasions of a searchspace, where M is a positive integer.

The network device determines N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a discontinuous reception DRX cycle, where N is a positiveinteger less than or equal to M.

The network device sends a power saving signal on the N targetmonitoring occasions in the search space, where the power saving signalis used to indicate power saving information of a terminal.

Embodiment 85: According to the communications method in Embodiment 84,a monitoring cycle of the search space is the same as a short DRX cyclein terms of a time length.

Embodiment 86: According to the communications method in Embodiment 84or Embodiment 85, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 87: According to the communications method in Embodiment 84,the N target monitoring occasions are N candidate monitoring occasionsthat are in the M candidate monitoring occasions and that are closest tothe on duration of the DRX cycle; and for each of the M candidatemonitoring occasions, a difference between a start time of the candidatemonitoring occasion and a start time of the DRX cycle is greater than orequal to a first preset value.

Embodiment 88: According to the communications method in Embodiment 87,a value of N is preset, or is configured by the network device for theterminal.

Embodiment 89: According to the communications method in Embodiment 84,the N target monitoring occasions are N candidate monitoring occasionsin a time window, a difference between a start time of the time windowand a start time of the on duration of the DRX cycle is equal to asecond preset value, and a difference between an end time of the timewindow and the start time of the on duration of the DRX cycle is equalto a third preset value.

Embodiment 90: According to the communications method in any one ofEmbodiment 84 to Embodiment 89, the power saving information includes atleast one of the following: whether the terminal monitors a PDCCH in aDRX cycle associated with the power saving signal; a minimum schedulingtime interval indication; a CSI measurement trigger indication; a BWPswitching indication; a search space and/or a CORESET that the terminalneeds to monitor in the DRX cycle associated with the power savingsignal; a monitoring cycle in which the terminal monitors the PDCCH inthe DRX cycle associated with the power saving signal; and skippingduration used by the terminal in the DRX cycle associated with the powersaving signal.

Embodiment 91: A communications apparatus is provided. Thecommunications apparatus may be a terminal, a chip in the terminal, or asystem on chip. The communications apparatus includes a processor and amemory. The memory stores instructions. When the instructions areexecuted by the processor, the communications apparatus is enabled toperform the following steps: determining M candidate monitoringoccasions of a search space, where M is a positive integer; determiningN target monitoring occasions from the M candidate monitoring occasionsbased on a time domain location of on duration of a DRX cycle, where Nis a positive integer less than or equal to M; and monitoring a powersaving signal on the N target monitoring occasions in the search space,where the power saving signal is used to indicate power savinginformation of the terminal.

Embodiment 92: According to the communications apparatus in Embodiment91, a monitoring cycle of the search space is the same as a short DRXcycle in terms of a time length.

Embodiment 93: According to the communications apparatus in Embodiment91 or Embodiment 92, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 94: According to the communications apparatus in Embodiment91, the N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle; and for each of the Mcandidate monitoring occasions, a difference between a start time of thecandidate monitoring occasion and a start time of the DRX cycle isgreater than or equal to a first preset value.

Embodiment 95: According to the communications apparatus in Embodiment94, a value of N is preset, or is configured by a network device for theterminal.

Embodiment 96: According to the communications apparatus in Embodiment91, the N target monitoring occasions are N candidate monitoringoccasions in a time window, a difference between a start time of thetime window and a start time of the on duration of the DRX cycle isequal to a second preset value, and a difference between an end time ofthe time window and the start time of the on duration of the DRX cycleis equal to a third preset value.

Embodiment 97: According to the communications apparatus in any one ofEmbodiment 91 to Embodiment 96, the power saving information includes atleast one of the following: whether the terminal monitors a PDCCH in aDRX cycle associated with the power saving signal; a minimum schedulingtime interval indication; a CSI measurement trigger indication; a BWPswitching indication; a search space and/or a CORESET that the terminalneeds to monitor in the DRX cycle associated with the power savingsignal; a monitoring cycle in which the terminal monitors the PDCCH inthe DRX cycle associated with the power saving signal; and skippingduration used by the terminal in the DRX cycle associated with the powersaving signal.

Embodiment 98: A communications apparatus is provided. Thecommunications apparatus may be a network device, a chip in the networkdevice, or a system on chip. The communications apparatus includes aprocessor and a memory. The memory stores instructions. When theinstructions are executed by the processor, the communications apparatusis enabled to perform the following steps: determining M candidatemonitoring occasions of a search space, where M is a positive integer;determining N target monitoring occasions from the M candidatemonitoring occasions based on a time domain location of on duration of aDRX cycle used by a terminal, where N is a positive integer less than orequal to M; and sending a power saving signal on the N target monitoringoccasions in the search space, where the power saving signal is used toindicate power saving information of the terminal.

Embodiment 99: According to the communications apparatus in Embodiment98, a monitoring cycle of the search space is the same as a short DRXcycle in terms of a time length.

Embodiment 100: According to the communications apparatus in Embodiment98 or Embodiment 99, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 101: According to the communications apparatus in Embodiment98, the N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle; and for each of the Mcandidate monitoring occasions, a difference between a start time of thecandidate monitoring occasion and a start time of the DRX cycle isgreater than or equal to a first preset value.

Embodiment 102: According to the communications apparatus in Embodiment101, a value of N is preset, or is configured by the network device forthe terminal.

Embodiment 103: According to the communications apparatus in Embodiment98, the N target monitoring occasions are N candidate monitoringoccasions in a time window, a difference between a start time of thetime window and a start time of the on duration of the DRX cycle isequal to a second preset value, and a difference between an end time ofthe time window and the start time of the on duration of the DRX cycleis equal to a third preset value.

Embodiment 104: According to the communications apparatus in any one ofEmbodiment 98 to Embodiment 103, the power saving information includesat least one of the following: whether the terminal monitors a PDCCH ina DRX cycle associated with the power saving signal; a minimumscheduling time interval indication; a CSI measurement triggerindication; a BWP switching indication; a search space and/or a CORESETthat the terminal needs to monitor in the DRX cycle associated with thepower saving signal; a monitoring cycle in which the terminal monitorsthe PDCCH in the DRX cycle associated with the power saving signal; andskipping duration used by the terminal in the DRX cycle associated withthe power saving signal.

Embodiment 105: A communications apparatus is provided. Thecommunications apparatus includes a first processing module and a secondprocessing module. The first processing module is configured to:determine M candidate monitoring occasions of a search space, where M isa positive integer; and determine N target monitoring occasions from theM candidate monitoring occasions based on a time domain location of onduration of a DRX cycle, where N is a positive integer less than orequal to M. The second processing module is configured to monitor apower saving signal on the N target monitoring occasions in the searchspace, where the power saving signal is used to indicate power savinginformation of a terminal.

Embodiment 106: According to the communications apparatus in Embodiment105, a monitoring cycle of the search space is the same as a short DRXcycle in terms of a time length.

Embodiment 107: According to the communications apparatus in Embodiment105 or Embodiment 106, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 108: According to the communications apparatus in Embodiment105, the N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle; and for each of the Mcandidate monitoring occasions, a difference between a start time of thecandidate monitoring occasion and a start time of the DRX cycle isgreater than or equal to a first preset value.

Embodiment 109: According to the communications apparatus in Embodiment108, a value of N is preset, or is configured by a network device forthe terminal.

Embodiment 110: According to the communications apparatus in Embodiment105, the N target monitoring occasions are N candidate monitoringoccasions in a time window, a difference between a start time of thetime window and a start time of the on duration of the DRX cycle isequal to a second preset value, and a difference between an end time ofthe time window and the start time of the on duration of the DRX cycleis equal to a third preset value.

Embodiment 111: According to the communications apparatus in any one ofEmbodiment 105 to Embodiment 110, the power saving information includesat least one of the following: whether the terminal monitors a PDCCH ina DRX cycle associated with the power saving signal; a minimumscheduling time interval indication; a CSI measurement triggerindication; a BWP switching indication; a search space and/or a CORESETthat the terminal needs to monitor in the DRX cycle associated with thepower saving signal; a monitoring cycle in which the terminal monitorsthe PDCCH in the DRX cycle associated with the power saving signal; andskipping duration used by the terminal in the DRX cycle associated withthe power saving signal.

Embodiment 112: A communications apparatus is provided. Thecommunications apparatus includes a processing module and acommunications module. The processing module is configured to: determineM candidate monitoring occasions of a search space, where M is apositive integer; and determine N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of onduration of a DRX cycle used by a terminal, where N is a positiveinteger less than or equal to M. The communications module is configuredto send a power saving signal on the N target monitoring occasions inthe search space, where the power saving signal is used to indicatepower saving information of the terminal.

Embodiment 113: According to the communications apparatus in Embodiment112, a monitoring cycle of the search space is the same as a short DRXcycle in terms of a time length.

Embodiment 114: According to the communications apparatus in Embodiment112 or Embodiment 113, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 115: According to the communications apparatus in Embodiment112, the N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle; and for each of the Mcandidate monitoring occasions, a difference between a start time of thecandidate monitoring occasion and a start time of the DRX cycle isgreater than or equal to a first preset value.

Embodiment 116: According to the communications apparatus in Embodiment115, a value of N is preset, or is configured by a network device forthe terminal.

Embodiment 117: According to the communications apparatus in Embodiment112, the N target monitoring occasions are N candidate monitoringoccasions in a time window, a difference between a start time of thetime window and a start time of the on duration of the DRX cycle isequal to a second preset value, and a difference between an end time ofthe time window and the start time of the on duration of the DRX cycleis equal to a third preset value.

Embodiment 118: According to the communications apparatus in any one ofEmbodiment 112 to Embodiment 117, the power saving information includesat least one of the following: whether the terminal monitors a PDCCH ina DRX cycle associated with the power saving signal; a minimumscheduling time interval indication; a CSI measurement triggerindication; a BWP switching indication; a search space and/or a CORESETthat the terminal needs to monitor in the DRX cycle associated with thepower saving signal; a monitoring cycle in which the terminal monitorsthe PDCCH in the DRX cycle associated with the power saving signal; andskipping duration used by the terminal in the DRX cycle associated withthe power saving signal.

Embodiment 119: A communications system is provided, including aterminal and a network device.

The terminal is configured to: determine M candidate monitoringoccasions of a search space, where M is a positive integer; determine Ntarget monitoring occasions from the M candidate monitoring occasionsbased on a time domain location of on duration of a discontinuousreception DRX cycle, where N is a positive integer less than or equal toM; and monitor a power saving signal on the N target monitoringoccasions in the search space, where the power saving signal is used toindicate power saving information of the terminal.

The network device is configured to: determine M candidate monitoringoccasions of a search space, where M is a positive integer; determine Ntarget monitoring occasions from the M candidate monitoring occasionsbased on a time domain location of on duration of a discontinuousreception DRX cycle, where N is a positive integer less than or equal toM; and send a power saving signal on the N target monitoring occasionsin the search space, where the power saving signal is used to indicatepower saving information of the terminal.

Embodiment 120: According to the communications system in Embodiment119, a monitoring cycle of the search space is the same as a short DRXcycle in terms of a time length.

Embodiment 121: According to the communications system in Embodiment 119or Embodiment 120, the target monitoring occasion is before the onduration of the DRX cycle, and is closest to the on duration of the DRXcycle.

Embodiment 122: According to the communications apparatus in Embodiment119, the N target monitoring occasions are N candidate monitoringoccasions that are in the M candidate monitoring occasions and that areclosest to the on duration of the DRX cycle; and for each of the Mcandidate monitoring occasions, a difference between a start time of thecandidate monitoring occasion and a start time of the DRX cycle isgreater than or equal to a first preset value.

Embodiment 123: According to the communications system in Embodiment122, a value of N is preset, or is configured by the network device forthe terminal.

Embodiment 124: According to the communications system in Embodiment119, the N target monitoring occasions are N candidate monitoringoccasions in a time window, a difference between a start time of thetime window and a start time of the on duration of the DRX cycle isequal to a second preset value, and a difference between an end time ofthe time window and the start time of the on duration of the DRX cycleis equal to a third preset value.

Embodiment 125: According to the communications system in any one ofEmbodiment 119 to Embodiment 124, the power saving information includesat least one of the following: whether the terminal monitors a PDCCH ina DRX cycle associated with the power saving signal; a minimumscheduling time interval indication; a CSI measurement triggerindication; a BWP switching indication; a search space and/or a CORESETthat the terminal needs to monitor in the DRX cycle associated with thepower saving signal; a monitoring cycle in which the terminal monitorsthe PDCCH in the DRX cycle associated with the power saving signal; andskipping duration used by the terminal in the DRX cycle associated withthe power saving signal.

Embodiment 126: A computer program product is provided. When thecomputer program product is run on a computer, the computer is enabledto perform the method in any one of Embodiment 77 to Embodiment 90.

Embodiment 127: A computer-readable storage medium is provided. Thecomputer-readable storage medium stores instructions, and when theinstructions are run on a computer, the computer is enabled to performthe method in any one of Embodiment 77 to Embodiment 90.

Embodiment 128: A chip is provided. The chip includes a processor, andwhen the processor executes instructions, the processor is configured toperform the method in any one of Embodiment 77 to Embodiment 90. Theinstructions may be from a memory inside the chip, or may be from amemory outside the chip. Optionally, the chip further includes aninput/output circuit.

Although this application is described with reference to theembodiments, a person skilled in the art may understand and implementanother variation of the disclosed embodiments by viewing theaccompanying drawings, disclosed content, and the appended claims. Inthe claims, “comprising” (comprising) does not exclude another componentor another step, and “a” or “one” does not exclude a meaning ofplurality. A single processor or another unit may implement severalfunctions enumerated in the claims. Some measures are recorded independent claims that are different from each other, but this does notmean that these measures cannot be combined to produce a better effect.

1.-79. (canceled)
 80. A search space monitoring method implemented by aterminal, wherein the search space monitoring method comprises:determining M candidate monitoring occasions of a search space, whereinM is a positive integer; determining N target monitoring occasions fromthe M candidate monitoring occasions based on a time domain location ofan on duration of a discontinuous reception (DRX) cycle, wherein N is apositive integer less than or equal to M; and monitoring, on the Ntarget monitoring occasions, a power saving signal indicating powersaving information of the terminal.
 81. The search space monitoringmethod of claim 80, wherein the N target monitoring occasions are Ncandidate monitoring occasions in a time window, wherein a firstdifference between a first start time of the time window and a secondstart time of the on duration is equal to a second preset value, andwherein a second difference between an end time of the time window andthe second start time is equal to a third preset value.
 82. The searchspace monitoring method of claim 81, wherein the time window is locatedbefore an active period of the DRX cycle.
 83. The search spacemonitoring method of claim 81, wherein the second preset value has beenpreconfigured for the terminal by a network device, and wherein thesearch space monitoring method further comprises negotiating, with thenetwork device, to determine the third preset value.
 84. The searchspace monitoring method of claim 80, wherein the power savinginformation indicates whether the terminal monitors a physical downlinkcontrol channel (PDCCH) in the DRX cycle.
 85. The search spacemonitoring method of claim 84, wherein the PDCCH comprises: a firstPDCCH carrying downlink control information (DCI) formats 0-0, DCIformats 0-1, DCI formats 1-0, and DCI formats 1-1; and a second PDCCHcarrying DCI format 2-0, DCI format 2-1, DCI format 2-2, or DCI format2-3.
 86. The search space monitoring method of claim 80, wherein each ofthe N target monitoring occasions is before the on duration and isclosest to the on duration.
 87. The search space monitoring method ofclaim 80, wherein the N target monitoring occasions are closest to theon duration among the M candidate monitoring occasions, and wherein foreach of the M candidate monitoring occasions, a difference between afirst start time of one of the M candidate monitoring occasions and asecond start time of the DRX cycle is greater than or equal to a firstpreset value.
 88. A communications method implemented by a networkdevice, wherein the communications method comprises: determining Mcandidate monitoring occasions of a search space, wherein M is apositive integer; determining N target monitoring occasions from the Mcandidate monitoring occasions based on a time domain location of an onduration of a discontinuous reception (DRX) cycle, wherein N is apositive integer less than or equal to M; and sending, on the N targetmonitoring occasions, a power saving signal indicating power savinginformation of a terminal.
 89. The communications method of claim 88,wherein the N target monitoring occasions are N candidate monitoringoccasions in a time window, wherein a first difference between a firststart time of the time window and a second start time of the on durationis equal to a second preset value, and wherein a second differencebetween an end time of the time window and the second start time isequal to a third preset value.
 90. The communications method of claim89, wherein the time window is located before an active period of theDRX cycle.
 91. The communications method of claim 89, furthercomprising: preconfiguring the second preset value for the terminal; andnegotiating, with the terminal, to determine the third preset value. 92.The communications method of claim 88, wherein the power savinginformation indicates whether the terminal monitors a physical downlinkcontrol channel (PDCCH) in the DRX cycle.
 93. The communications methodof claim 92, wherein the PDCCH comprises: a first PDCCH carrying DCIformats 0-0, DCI formats 0-1, DCI formats 1-0, and DCI formats 1-1; anda second PDCCH carrying DCI format 2-0, DCI format 2-1, DCI format 2-2,or DCI format 2-3.
 94. A terminal device comprising: a memory configuredto store a computer program comprising instructions; and a processorcoupled to the memory, wherein when executed by the processor, theinstructions cause the terminal device to: determine M candidatemonitoring occasions of a search space, wherein M is a positive integer;determine N target monitoring occasions from the M candidate monitoringoccasions based on a time domain location of an on duration of adiscontinuous reception (DRX) cycle, wherein N is a positive integerless than or equal to M; and monitor, on the N target monitoringoccasions, a power saving signal indicating power saving information ofthe terminal device.
 95. The terminal device of claim 94, wherein the Ntarget monitoring occasions are N candidate monitoring occasions in atime window, wherein a first difference between a first start time ofthe time window and a second start time of the on duration is equal to asecond preset value, and wherein a second difference between an end timeof the time window and the second start time is equal to a third presetvalue.
 96. The terminal device of claim 95, wherein the time window islocated before an active period of the DRX cycle.
 97. The terminaldevice of claim 95, wherein the second preset value has beenpreconfigured for the terminal device by a network device, and whereinwhen executed by the processor, the instructions further cause theterminal device to negotiate, with the network device, to determine thethird preset value.
 98. The terminal device of claim 94, wherein thepower saving information indicates whether the terminal device monitorsa physical downlink control channel (PDCCH) in the DRX cycle.
 99. Theterminal device of claim 98, wherein the PDCCH comprises: a first PDCCHcarrying DCI formats 0-0, DCI formats 0-1, DCI formats 1-0, and DCIformats 1-1; and a second PDCCH carrying DCI format 2-0, DCI format 2-1,DCI format 2-2, or DCI format 2-3.